Here are some of my favorite links

Midwifery Today: A wealth of information on natural, normal birth, VBAC, and more
The HypnoBirthing Institute
The Coalition for Improving Maternity Services
Massachusetts Friends of Midwives: Support your local midwives!
Ina May Gaskin, Midwife: The mother of modern midwifery
Let Your Monkey Do It: new dad Skylar Browning talks about natural childbirth.
Henci Goer, author of The Thinking Woman's Guide to a Better Birth - a must read!

HypnoBirthing^® - Taking the World by Calm