I just came across this site called
Pandora. You put in a name of an artist or song you like and it finds other songs or bands that you might also like. It's pretty cool stuff. I've already found 9 bands that I might be interested in. The first 10 hours are free and after that it's $36 a year. The only problem is that the god damn RIAA limits the number of songs you can listen to in 1 hour and it doesn't let you repeat songs.
Here's a list of bands I've found with it that I might like:
Shadows Fall
Opeth
Swift
Trust Company
Unearth
Killswitch Engage
Soilwork
Shortie
Kids In The Way