Rixa Freeze of "Stand and Deliver" has posted her doctoral dissertation on Unassisted Childbirth, and it is really, really good. Go check it out! I'd post the link but this computer won't let me, but if you go to the site above, you'll see the link on your immediate right. I'm about two-thirds of the way through the document, and it is really fascinating. I'm learning a lot, and I think you will too!
Unassisted childbirth is not a current goal for me (I love my midwives!), but it's a fascinating topic, and one that's always a real possibility as an unintended accident that is quite common when parents (especially repeat parents who are expecting longer labors) call the midwife too late. So it could happen to anyone - including me! A fun possibility, but again, I love my midwives and would rather have them there.
For anyone who's interested, though, I have started a small sidebar on unassisted childbirth (UC), also called freebirth, and will be posting informational sites as I run across them.