Have any of you guys heard of pandora?
www.pandora.com. The site lets you put in a band or a song that you like then makes a custom "station" of songs that you can listen to and rate to make the station more to your tastes. It seems to have a pretty extensive library backing it too. Pretty sweet.
Only thing that's irked me so far is it bugs you for a free registration after a while and only allows you to skip only a certain amount of songs an hour (probably a legal thing though).
I've been playing with it for about a day and I've already got a couple bands I really like out of it.
Give it a shot!