One doesn't have to try very hard to find amazing amounts of latin music on the internet. The majority of this is salsa. And I mean this in the narrow sense of the word as it is accurately described here. Personally I am inclined to prefer the music of pre-salsa times, and for this I refer you gladly to the listentoyourears blog (which in my opinion is on a level of its own*).
Strangely the salsa artists I like always turn out to have Cuban origins. Apparently the son & rumba roots are difficult to lose. This is the case with both Papaito and Monguito, who have unfortunately both passed away (in 2000 and 2006). They both feature on this classic collection from the SAR label with two songs. The remaining tracks are by another artist with Cuban roots, SAR-(co)founder Roberto Torres, and by Conjunto Crema (no Cubans there, I think).
Cañonazo seems a bit exaggerated, but it's certainly an enjoyable collection.
SAR 1041 (new link November 10, 2012)
*despite the use of rapidshare....