NoiseTrade.com offers hundreds of free albums (with a classy option to 'tip' the band for their album; like busking online, love it!) Lots of great stuff here, many established artists, and many more who deserve some notice.
Definitely check out The Wooden Birds HERE.
The Apache Relay HERE.
The Civil Wars 'Live' HERE.
Brandi Carlile HERE.
The Oxygen Ponies HERE.
Oh yeah, and the hundreds of others I haven't found yet. Be sure to let me know if there are any that deserve special recognition (e-mail me at onehundredyears@gmail.com). Thanks!