My idea is that there is music in the air, music all around us; the world is full of it, and you simply take as much as you require. --Sir Edward Elgar
All world music searches should start with the Garland Encyclopedia of World Music.
For most topics, you will also find good information in the Grove Music Online reference database. Both of these are scholarly works, well recognized in the field of music research.
You'll find links to these and other research resources in the Reference Sources box below.
The Garland Encyclopedia is also available in print on the Reference shelves under the number REF ML100.G16. You may find this works well for browsing and focusing your topic. CDs with sound clips to go with the text are available--just ask at the Research Help Desk.