If you go the book route. Check out
www.half.com It's ebay's used book store (music and movies as well). You can get books there cheaper than any other place on the net.
As far as learning goes, I am in the same boat. I've never taken a class and have been embarrased by not knowing all the terminology. I know that I have a good eye when it comes to composition but I have been trying to learn the terms and rules. I've read and read and still get confused so know I write myself notes (as if I were taking notes for a class).
Besides that I would just keep taking pictures and let other people see them to see what you can do better. (Something I should be doing more of)