Gimli, you can download a copy of the mIRC chat sorftware (for free) from http://mirc.com/. At the left in blue is an option to download. Just follow the prompts. You will need to select your country and you will be asked to register your copy.
I found the software easy enough to use after experimenting with it for a while. It contains online help if you need it.
Planet-Tolkien.com's chat room is on the server called sorcery and is the channel #tolkien.nn[Edited on 16/12/2002 by Allyssa]