I give an enthusiastic second to "The Care and Keeping of You." I love those American Girl books -- they have one on almost every topic (puberty, friendship, feelings, starting middle school) and they are very well-done and sensitive yet realistic.
Some 9-year-olds are getting their periods already, so I applaud your decision to be proactive and talk to your daughter now. I think it would be awful to get your period for the first time and not know what's going on!
My personal philosophy is that if I try to drop things into the conversation whenever they come up naturally, my kids don't make too big a deal about them. We have openly discussed body parts, how babies are made, etc. since they were little, and so they don't see it as a big secret.
Speaking of that, there are two great books to explain the birds and the bees -- "What's the Big Secret?" by Marc Brown (the Arthur guy) and Laurie Krasny Brown, and "It's So Amazing! A Book About Eggs, Sperm, Birth, Babies, and Families" by Robie Harris.
Good luck!