As a result of visiting Spain many times, and learning the language (to a degree) I have been exposed to a lot of music new to my ears from the Spanish world. Although not all of it does not come from Spain (some from Latin America) I would not have had access to this music had I not had this interest in Spain. So I would like to nominate 5 artists that would get in my top 10. I have tried not to duplicate Madridman's list, so unfortunately no Ketama here!!
Chavela Vargas - incredible vocalist from Mexico
Joaquin Sabina - Madrileño originally from Buenos Aires. Brilliant lyrics, superb mixer of different music styles
Guillermo Portabales - A great source of traditional Cuban music. He is sadly missed.
Paco de Lucía - The master of the guitar
K'jarkas - Bolivian/Andes folk heroes.

I would like to hear other people's faves and suggestions. (It's a good way of getting exposure to new music)