Have you discovered Michael Craton? He's a historian who lives in Canada and teaches at the University of Waterloo, and I'm almost positive he's Jamaican. He has written exceptional books about the history of migrations to Jamaica, the Caymans, and the Bahamas, plus a lot of journal articles on other Caribbean nations.
He hasn't focused a lot on the diaspora, but he's definitely a good starting point for people (especially of African descent) tracing lineage back to the Caribbean. A lot of his texts are out of print now, but you can usually obtain them through ILL easily enough.