Spanish and Latinamerican writers don't use really so much slang, they just use different synonyms for the same thing, and all those words are acepted by the Real Academia, which is common for all the countries where Spanish is the oficial language, their page is http://www.rae.es and they have a dictionary http://www.rae.es/NIVEL1/buscon/AUTORIDAD2.HTM,
Be sure to select the actual dictionary 1992, or you won't find almost anything

I forgot to thank Boqueron about the Lorca CD, I'll look for it.
There is also a CD of Enrique Morente called Lorca and the most innovating one is Morente + Lagartija Nick singing Leonard Cohen songs with some Lorca words.

Actually, the chilean book I was reading did use quite a bit of slang. Typically though, it is the expressions used in a place and jokes that are essentially cultural references that are the most difficult to pick up on, unless you really know a place.

As much as I enjoy Vargas Llosa, he is difficult to read in English. He has an incredible vocabulary, good for getting ready for that GRE. In Spanish though, he makes tons of references I would completely miss if I hadn't "inherited" some of my mother's books (she and my Dad lived for several years in the region of Peru he frequently writes about ) with lots of little notes written in the margins - explanations of phrases and words that her Peruvian friends explained.

I did a little research on the Gitanos Cantan Lorca album and found that it is put out by Mercury Records. Hopefully that'll help anyone looking for it.