Let's not forget the basics:
http://www.lightandmatter.com/area1book1.html
Clearest textbook I have seen to date and it's free for the downloading.
This one, or Thompson's original version, can be had at little cost in used book shops:
http://www.amazon.com/gp/product/cus...views.start=11
As an incorrigible tilter at windmills and kicker of sacred cows I am compelled to reccommend this text. On the other hand, it probably should be read in conjunction with a standard calculus textbook, many good ones of which are available from vendors of used books.