May I suggest you move this thread into a better section of the forum (this is for workbenches), and you might get some more replies if you do so! There's a section of the forum dedicated to musical instruments here:
MUSICAL INSTRUMENTS - Woodwork Forums
As for the fingerboard, rosewood, ebony, maple are all commonly used and would all suit quite well (do a quick internet search to see what they do to the tone of the guitar). Though I don't know what timbers are available to you in Argentina.
The body - mahogany (used on many high end gibson's) and/or maple are a few.