A friend of mine who planned to have a natural childbirth with me present had me read Ina Mae's Guide to Natural Childbirth. My memory is that it was a little bit hippie granola, but not as much as I'd feared, and did a good job of demystifying the process without a bunch of scare stories. It also had a lot of personal accounts. It might be worth a look regardless of what sort of birth you're planning. (Please don't take the rec as advice to go natural.)

For the same purpose, I also read Baby Catcher by Peggy Vincent, a widwife's memoir. I recall that it was entertaining, had lots of birth details, and was generally uplifting and positive without being sappy.