Hi alamilejida!
"Where should I start?" is a big question. I have been playing for about 2 years as a hobbyist. You posted on the books, videos page so my advice is focused here. The first place to start I was told was on my sound, developing distinct and strong sounds for each of the tones ~ open, slap, muff, bass, tip. I think Michael Spiro's DVD, Introduction to the Conga Drum, is the mass market product that does the best job in both explaining and showing how to get strong tones, along with providing excellent exercises. I bought this after playing a year and I review this video every couple of months and use a few of Spiro's exercises through the week. He gives the viewer a good review of the ideas behind Cuban music and of a few genres in Cuban conga drumming: 6/8 bell, clave, bembe, rumba guaguanco, salsa.
http://www.amazon.com/Introduction-Cong ... 733&sr=8-1For learning rhythms I think Alan Dworskys book with CD, Conga Drumming: A beginner's Guide to Playing with Time is really quite helpful.
http://www.amazon.com/Conga-Drumming-Be ... 0786623462 I am also quite a fan of the rhythms presented in Tomas Cruz's first two DVD/book combos though the technique he shows for getting tones is a bit rough for my hands.
Best to you ~ Peter