Normally I wouldn't immediately recommend you download jazz and world music albums. Unlike other genres, jazz, world and classical have so much intricacies that you really need to hear it on a stereo to get the full meaning of the music. Listening on your computer speakers (no matter how expensive) just doesn't cut it. But since the demise of the record store there are few places to actually get physical CDs. So downloading is the best and only way to go.
I wanted to suggest a couple of albums you could download from iTunes that would satisfy your listening pleasure for awhile and give you a little more insight on what to discover next. I've tried to list titles that I haven't talked about before. I hope you have the time to check this out soon.
1) Old and New Dreams Playing (ECM Records)
2) One For All Upward and Onward (Criss Cross)
3) Lars Danielsson & Leszek Mozdzer Pasodoble (ACT Music)
4) Fred Hersch Trio+2 (Palmetto Records)
5) Nine Horses Snow Borne Sorrow (Samadhisound)
6) Sam Yahel Hometown (Positone)
7) Eric Alexander Primetime (High Note)
8) Polar Bear Polar Bear (Tin Angel Records)
9) Jon Hassell Last Night The Moon Came Dropping Its Clothes In The Street (ECM Records)
10) Femi Kuti Day by Day (Mercer Street Records)
Since you will have a chance to listen to a sample of each song on iTunes I think you will get a good idea of the entire album. Have fun and happy listening.