I don't know if you like this. I've known artists who said good things about it:
http://www.amazon.com/gp/aw/cr/0060926716/ref=aw_d_cr_books
Same thing, different site:
http://www.constructingtheuniverse.com/

Browsed quickly down the amazon trail while I fed the baby and read amongst the reviews and offerings that origami paper folding is a nice kind of hands on side trip for this subject. Man I like seeing all the great things there are to learn.


Youth lives by personality, age lives by calculation. -- Aristotle on a calendar