I haven't found much on Caribbean folk music. Alan Lomax did a fair amount there, and he produced a remarkable Town Hall concert in New York in 1946. Performers included The Duke of Iron, Macbeth the Great, Lord Invader, and Gerald Clark and his Invaders. I have a feeling that these performers, whose names are on many well-known Caribbean songs, drew their works from traditional sources.

The only early collection of Caribbean songs I know of, is The Island Song Book (1927), by John T. McCutcheon (1870-1949). I've been trying to get a reasonably-priced copy of that book for years, with no luck.
-Joe-