One can reach the OpenACS channel at irc://irc.freenode.net/#openacs. Mozilla users (with a complete install) can simply follow this link. Others open their favorite IRC client and connect to the irc.freenode.net server. Then join the #openacs channel.
If you don't have an IRC client yet, find one that suits your needs at IRC.org. This short IRC primer is recommended reading for all IRC newbies.
Be sure to enter your IRC nick name as your screen name on openacs.org. Our log bot will then link your nick to your openacs.org profile in the logs. To enter your nick name go to your account and follow the update link.