The "BPL Bible" is an excellent source of information to the lightweight, and those looking to become lightweight backpacker. The text is very in depth and may be a bit intimadating for new comers (But that's just my opinion, I grew up reading MAD magazine). Which is why I also recommend:
"Lighten Up! A complete handbook for light and ultralight backpacking"
This book is short, humorous and provides an excellent base knowlege for going light. This is the first book I picked up when I first thought about going light.
Get both books, and get yourself a digital kitchen scale for weighing items in your pack. It's an eye opener. If you have an item that maxes out the 5 lb (2.2 kg) scale weight limit, you probally want to leave it at home or find something lighter.
Welcome to the site, Mark. I've found it to be a gold mine of knowlege and advise from a community of people who share a common love.