There are some good ones on youtube.com, but title or performer needed to find them (very few have 'Jamaica(n)' in the youtube lists).
Be careful of websites promising Jamaican songs, some are virused.

Titles can be found at mentomusic.com (an excellent site for lyrics, history and lists).

Also see the thread Jamaican folk music for lyrics, references and remarks about some singers.
jamaican folk music
(For some reason not included in the list at top of this thread)