anybody here experienced with iChat?

I don’t normaly like to ask general computer questions like this here, but I am at a complete loss. I quit AOL some time ago because they were charging me an exhorbitant amount of money for nothing (OK obviosly one feature.) but the one thing I miss is AOL instant messanger so I can talk to my freinds online.
One neat feature on the mac OS X is iChat. Sometime ago I entered a screan name (I guess under the AIM thing thinking I could use it as AIM.) “monobrow123” but I was never able to get it to work. AIM is really not that important in my life so I just ignoreed it and went about my buisiness.
Now, I was trying to have a conversation with a freind of mine over the phone, but he gets unbeleivably poor reception. As a result we thought it would be easiest to converse via e-mail. This sucks!
At this point I figured I should try to get iChat to work and see if we could hook up that way. the problem is I don’t remember my iChat password so I can’t log into my old account. Worse yet, I can’t figure out how to create a new account (this seems like it would be a really poor buisiness strategy.).

What can I do?  Oh yeah, naturally he has a PC.

Create an AIM screen name.

Can you use AIM for Mac or, better yet, Skype?

You can download and install Yahoo IM at no charge.