Quite a lot of you signed up for emusic's trial (50 free mp3s, no charge if you cancel within 14). If anyone has any serious complaints let me know. I don't mean in the sense that I can be your customer service rep, but if I plug something I want to know that it's a decent service so as not to lead people astray.
Some artists I've enjoyed recently which have at least some of their stuff on emusic.
Matt Pond PA
Pretty Girls Make Graves
The Essex Green.
The New Pornographers
For classic music lovers, they have a massive Naxos catalog. And, since it's basically a quarter per song depending on how the music is sliced up on the CDs you could be downloading massive amounts of classical music for cheap - a quarter per movement, a buck a symphony for lots of stuff.