BB reader Jeff Gates sez:
Smithsonian Global Sound is to world music what iTunes is to popular music. Just like iTunes, each song is 99 cents. You can search in the normal way (by text string) But you can also browse by geographic location, instrument, and cultural group (which is pretty cool). And, of course, you can hear samples before you buy. Take a look at their Synchrotext feature, which allows you to follow real time translation and commentary of oral performances.