there is SO much great reggae.
i would start with an older compilation called respect to studio one.
finding that is like finding a window onto a motown that you didnt know about.
to wit:
http://www.amazon.com/Respect-Studio.../dp/B00000045A
a primer on this earlier history of the music:
http://niceup.com/history/ja_music_59-73.html
o yeah: see "the harder they come" too---you dont want to drift away into the american stoner take on reggae--it is linked to social conditions in ja very tightly and it's better not to forget this.
or maybe you'd like dub:
http://www.dub.com/
a nice introduction with tons of stuff to stream.
there is a ton more, but you have to start somewhere and these are good somewheres, i think.