There are a number of excellent guides to doing various things with Irssi, and there is no need to repeat them here. Try checking through the following list:

• Official Irssi FAQ
• Official Newbie Startup Guide
• Using Irssi Efficiently with GNU Screen
• Understanding Split Windows in Irssi
• Irssi Settings and their Meaning

The most obvious location is http://scripts.irssi.org, but there are some useful scripts that are not currently in the repository.

You can also try:

• https://github.com/coekie/irssi-scripts/
• https://github.com/shabble/irssi-scripts/
• http://www.explodingferret.com/linux/irssi/
• https://github.com/msparks/irssiscripts
• http://wouter.coekaerts.be/site/irssi/irssi
• http://mindboggle.us/irssi/scripts/perl/
• https://github.com/mauke/irssi-scripts
• https://vague.se/irssi/scripts
• http://juerd.nl/site.plp/irssi
• https://github.com/mauke/irssix-modules
• http://anti.teamidiot.de/static/nei/*/Code/Irssi/
• http://billnye.blinkenshell.org/irssi/
• https://github.com/rfreebern/irssi-revolving-door