emusic is wonderful! They've got me absolutely hooked with the variable bit rate mp3's, no DRM, extensive indie catalogue (awesome spoken word and comedy stuff! Neil Hamburger!!!), and ridiculously low prices compared to the Apples and Sonys of the world. Can't beat 'em.
I would really urge the OP to give 'em a thorough look. Type in the name of an artist you're interested in and then when it doesn't come up, click on the "artists similar to" link and see what goldmines you can uncover.