I've been trying to sample a lot of the more obscure, lesser-known acts for Coachella in April, and I've found some good ones via Myspace.
Whitest Boy Alive and Hockey are good for soul-tinged pop rock.
Little Dragon is a good mellow act.
Delphic borderlines on dance music/techno. Very synthy, but very very good.
Coachella on their facebook linked this website, to get a small sampling of each act. Good to put the thing on shuffle/random and just let it play...
http://bit.ly/dyCK38