James William Roy's Paper Valentines got reviewed: FREE MP3s, too!
The Folks at Ampeater Music don't necessarily "get" Rock Band, but they totally dig on my music and I love 'em for that. They've got a bunch of my songs up for free, so go get 'em: http://ampeatermusic.com/aem103
They're a great site for learning about new music: they put up a pair of free songs (they call them Digital 7"s) and write up a really involved review of the artist. They only put up artists that they like, and mostly that they've invited. I'm a big fan.