OK guys, so just a few points to make. This tutorial will go through the process of explaining how to install and set up irssi on a Debian server. I am by NO means an expert, so feel free to ask any questions, but bear in mind I may not be able to answer 
This is supposed to be a supplement to MikeD's excellent tutorial, and will go into greater detail of the configuration of irssi. You can find MikeD's irssi tutorial here
It will detail installation and configuration to get you to a point where you are able to auto join servers and channels. I will also go through the addition of various script add ons to get the shell looking more similar to what you will be used to on mIRC or XChat.
It will not cover setting up RSS from tracker announce channels, although saying this, once you are in the required announce channels, then setting RSS up should just be a matter of downloading an installing a perl script from the tracker.
I have compiled this tutorial from various sources, to see a full list please look at the end of the post.
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Installation
OK, so to start off we need to create an ssh connection into your server. I will be working from this on the basis of using a Debian Terminal, but the process should work equally well through Putty if you are using a Windows PC. (Please note, if you are planning to run irssi through Putty, for chatting purposes as well as RSS, then I reccomend you update to Putty Tray, as this will make URLs clickable. You can download it from here)
Please see MikeD's tutorial on how to ssh into your sever via Putty.
To initiate an ssh connection through terminal: [Do not type the $]
Code:
$ ssh -p [port] [user]@[host]
-p [port] is only needed if your ssh port is not default (normally 22). You will be prompted for your password. Enter it and press enter. You should come to a screen looking like this

A lot of servers already have irssi installed, if you followed MikeD's Debian server setup, you will have it. If not you will need to download and install it
DO NOT INSTALL IF YOU ALREADY HAVE IRSSI INSTALLED - CHECK FIRST.
Code:
$ sudo apt-get install screen irssi
and then start irssi in a screen
Code:
$ screen -S irc irssi
This will start irssi in an attached screen named irc.
You will find yourself looking at irssi in its default state, not connected, with two blue bars:

Basic Configuration
OK, now we can start to configure your basic irssi setting, nicks etc. When we get to the point of adding servers, we can automatically add a server specific nickname, however, not an alternate nick name. As such, I would suggest not setting these as your T-I details. We do not want you to accidentally connect to a tracker IRC with your T-I username!
OK, so in the irssi screen type:
Code:
/set alternate_nick someothernick
Code:
/set user_name somenick
Code:
/set real_name somenick
Your irssi screen will confirm and should look similar to this:

Auto Adding Severs and Channels
We can now start to add severs to autostart, and channels to autojoin. By default, your irssi folder will be located in ~/.irssi/ and in there you will find a config file, where all of these set up details are stored. We do not need to modify that file as these commands are added in the irssi screen, but if you want to ever check the details, then take a look in there.
So to get the ball rolling.
First we need to define a network alias, that you can relate all the following commands to.
Code:
/network add -nick [nick to join server with] [server name]
So my actual command line, for T-I irc would be:
Code:
/network add -nick Jameo Aust
as we are on the AustIRC network 
The next step is to add a server to that network alias so irssi knows how to connect. So:
Code:
/server add -auto -network Aust irc.austirc.net 6667
So that command line basically says, add a sever to autojoin on the Aust network with the server address and port.
Next we want to add any autojoin commands that are necessary for the network, for instance logging onto NickServ:
Code:
/network add -autosendcmd "/msg nickserv identify [yourpass]" Aust
We then need to set the channels to autojoin upon connection to the network
So to join #torrent-invites
Code:
/channel add -auto #torrent-invites Aust
If you need to join a channel with a key, then add the key after the network alias. i.e
Code:
/channel add -auto #torrent-invites Aust [key]
Add any further channels you wish to join, do so in the same way.
You should now be set up to auto join servers and channels, and autosend any commands. Your irssi screen should look something like this:

if your quit irssi with /quit, and then restart with
screen -S irc irssi
You should auto join the servers and channels
Modifying IRSSI with the Addition of PERL Scripts
Ok, so I will now show you how I have my irssi set up, so it looks a little more familiar, and is a little more user friendly.
The scripts I will be using are:
nicklist.pl - Adds a list of channel users
adv_windowlist.pl - modifies status bar
usercount.pl - Adds total users
openurl.pl - fixes URL link problems (links containing ?/!)
hilightwin.pl - echoes any hilight into the current window
trackbar.pl - marks the positions you where at when you were last on a channel
xchatnickcolor.pl - a script to mimic xchats coloured nicknames
I also use a theme, xchat.theme, this just rearranges the layout and colour.
Ok to start off we have to get the scripts downloaded to your server. To do this, we need to detach your irssi screen.
This is accomplished with Ctrl + A + D, or on some Macs, Ctrl + Shift + A + D, you are now back into your ssh shell.
We now need to create the directory to store you scripts in. To autorun scripts they need to be located in ~/.irssi/scripts/autorun
so to create the relevent directories (/.irssi/ should already be there):
Code:
$ mkdir ~/.irssi/scripts
Code:
$ mkdir ~/.irssi/scripts/autorun
Now cd into that directory:
Code:
$ cd ~/.irssi/scripts/autorun
and get the relevant scripts
Code:
$ wget http://scripts.irssi.org/scripts/nicklist.pl
Code:
$ wget http://scripts.irssi.org/scripts/usercount.pl
Code:
$ wget http://scripts.irssi.org/scripts/trackbar.pl
Code:
$ wget http://dave.waxman.org/irssi/xchatnickcolor.pl
Code:
$ wget http://scripts.irssi.org/scripts/openurl.pl
Code:
$ wget http://anti.teamidiot.de/static/nei/*/Code/Irssi/adv_windowlist.pl
Code:
$ wget http://scripts.irssi.org/scripts/hilightwin.pl
We also need to download the theme script to the relevent directory.
cd into the main irssi folder
Download the xchat theme
Code:
$ wget http://irssi.org/themefiles/xchat.theme
(You can actually wget files without cd'ing into the directory with $ wget [path] [location], but there will be fewer mistakes doing it this way
)
So now all the scripts should be downloaded into the autorun folder, and the theme file into the .irssi folder.
We can now go back into the irssi screen
We now need to load the theme's and scripts, and make some modifications to the layout.
hilightwin.pl
To load the script
Code:
/script load autorun/hilightwin.pl
We now need to modify the layout to give a separate window for the hilight messages to be echoed to
Code:
/window name hilight
Don't forget to save the layout:
/layout save
This will create a split window at the top of every window, with a size of 6 lines, and named hilight.
Your irssi should now look something like this.

If you have done everything correctly, any hilighted text should be echoed into the current window. Please note the window MUST be named 'hilight' so the script knows where to echo the hilights to!
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adv_windowlist.pl
Load the script as before
Code:
/script load autorun/adv_windowlist.pl
ADV will automatically start a new status bar, we can remove the old one:
Code:
/statusbar window remove act
And we can tidy up the new status bar to make it look a little nicer
Code:
/set awl_display_key $Q%K|%n$H$C$S
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usercount.pl
Again, load the script:
Code:
/script load autorun/usercount.pl
and update the status bar to include usercount:
Code:
/statusbar window add usercount
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trackbar.pl openurl.pl and xchatnickcolor.pl
To initiate these scripts, all we have to do is load them:
Code:
/script load autorun/trackbar.pl
Code:
/script load autorun/openurl.pl
Code:
/script load autorun/xchatnickcolor.pl
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nicklist.pl
So this is the most difficult script to get working, and it requires a second terminal window.
Before we move onto this script, I would just like to load the xchat theme:
and save
Now, moving onto nicklist.pl, in your main irssi screen, load the script.
Code:
/script load autorun/nicklist.pl
We now need to start a fifo for the other terminal window to listen to:
We now need to tell the other terminal window to listen to the fifo (now is the time to resize and reposition your second terminal window [which will display the nick list] to the right hand side of your main irssi screen.
Make sure you have logged onto ssh on this window as well, and give the listen command
Code:
$ cat ~/.irssi/nicklistfifo
You also need to set the height and width of the window for the script, do this in the irssi screen
Code:
/SET nicklist_height <height of nicklist>
Code:
/SET nicklist_width <width of nicklist>
Where the height and width are given as number of lines and characters respectively.
You can now start using the fifo, with this command in the irssi screen
Hopefully now, your irssi should be fully set up, and looking something like this

So what are we looking at here. In the above image I have labelled the relevant parts.
1) This is your split window, named hilight, where all your highlighted text and PMs go (as you can see I was having a conversation with BK in PM as I was taking this image.
2) The main chat window.
3) The second terminal for nicklist.pl, where nicklist is echoed.
4) Status bar, top, with username and modes/channel number/network/and channel modes/ alias/current channel name, and usercount.
5) Status bar, bottom, this shows all the channels you are part of, and their relevant number.
6) This is where you type :)
Just to run through a few useful commands:
MAC USERS - YOU WILL NEED TO INITIATE META TAGS TO USED ALT/OPTION KEY
Terminal -> Preferences -> Keyboard
To change through the channels you can either:
Alt+channel number, or scroll through with Alt+arrowkeys
Alt+PgUp/PgDn - scrolls through converstation
/wc - Closes current window
You can set autologging to on, and change the path with
/SET autolog ON
/SET autolog_path.
Full list of irssi commands and alias
Download irssi scripts
Sources:
http://www.torrent-invites.com/tutor...ver-setup.html
A Guide to Efficiently Using Irssi and Screen | quadpoint.org
Tech newbie: How to install and use Irssi (Linux IRC Client)
Irssi settings guide
Irssi - The client of the future
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Well, thats it, I hope you have found this tutorial useful. If you have noticed any errors, please tell me and I will update, also any questions please ask.
If you think an additional screenshot would be useful somewhere, again please tell me and I will try to get one sorted.
Cheers
~Jam