After looking for an IRC channel dedicated to discussing InDesign, typography, book design, graphic design etc. I had to give up and instead create one myself - #indesigning on irc.freenode.net.
If you are new to IRC, you can read the IRC Prelude to get a better idea of what it is about, but in short it is a chat room you can connect to, where hopefully there will always be someone around to talk with, share ideas, get help, launch exciting projects etc.
If you are on a mac, take a look at Colloquy which is an excellent free IRC client. On Windows you might want to have a look at mIRC.