This review could be pages and pages of lists, but since it's Africa that got things started, I'll just mention that as an example....
If you listened to your parents records in the sixties and your parents were hip, you probably got a taste of Jobim from Brazil and Township SA's Hugh Masakela; maybe even Miriam Makeba from Joburg doing the chart-burner "Pata-Pata"... But non-first-world music didn't get a fair listen till later, really.
For me, World Music began in earnest circa 1984, with seeing footage of Senegalese brother-band Toure Kunda performing "Salya" live in some african venue ... In an era where Punk's energy had faded and music was getting the epoxy-polymer treatment from the big labels, Toure Kunda was a knockout punch... A beautiful groove, nicely laced-together melodies, and most of all infectious energy and pace ... thoroughly unforgettable. Contemporary Saharan trance-groove band Tinariwen certainly share a musical background with Toure Kunda.
Salif Keita, Baaba Maal, Yousou N'Dour, Bembeya Jazz, Zani Diabate and the Super Djata Band, Orchestra Baobab, Cheikh Lo, Wasis Diop, Oud-Master Hamza el Din, Angelique Kidjo, and Marie Dualne's Zap Mama are all now part of my core musical menu, in heavy rotation. And it cannot be overstated that, quibbles aside, the 'World Music' concept of the middle eighties brought immeasurable musical wealth to the west, and yes, to the world.
This October 1994 version of the World Music Rough Guide is worthwhile for it's inclusiveness in that era; for 2011 there is a more current edition that I'll also be picking up. The World has changed in those fifteen years, and we may need two rough guides to cover the changes.
Almost forgot, you can never talk African music without mentioning Mahlathini The Lion Of Soweto, and his Mahotella Queens.
Gil Scott Heron told us, way back when : What's the Word ? Johannesburg.