I break it down into three groups:
1) the original stuff outta Jamaica and the UK in the '60, like the Skatalites, The Pyramids, and early stuff by reggae artists like Toots and the Maytals and Desmond Dekker.
2) the revival around 1980 (Specials, The Selector, Madness)
3) everybody else since then
My all-time favorite? Specials, Specials, SPECIALS!!!!
If you like the Specials, definitely check out The Selector. They were on the same label, 2 Tone, and were unique (at that time) in that they had a chick singer.
And you can find lots of compiliation CDs of ska.
It's happy music... have fun!
Yeah, well, you know, that's just, like, your opinion, man. --The Dude