Oh, finally a thread I can chime in on, being that I'm an IRC god and all.
I don't know of any channels for studio recording that exist, but for a time, Scenaria in Tech Talk tried to start a Group DIY channel on a network who's name now escapes me.
As for myself, I usually hang out on Nightstar.net, which is a smallish and very stable network. If anyone really wants to, it would be a simple matter to start a channel there. In fact, I have a channel of my own if anyone would like to pop in in the course of experimenting. I can give any further help and instructions from there.
irc.nightstar.net
#studioconsul
If anyone wants some basic instructions on using IRC:
http://www.nightstar.net/dark_tiger/ircguide.html
gwalla is an old friend of mine, and an IRC op on Nightstar (an admin, essentially).