I have been slowly accumulating a library of books on pregnancy, childbirth, and child-rearing. For some reason I consciously avoided "What to expect when you're expecting". It seemed to be part in parcel of a whole slew of pregnancy inevitabilities in my community, like prenatal pilates DVD's and baby bjorns.
Back when getting knocked up was still in its idea phase, kiff bought "Pregnancy and Childbirth". It has some great pictures in it, but on close inspection, much of Sheila Kitzinger's information seemed anecdotal rather than scientific. I finally tossed it aside when I read the breathless chapter on circumcision that claimed it, in some circumstances, could KILL your baby.
A friend of mine handed down "Girlfriend's Guide to Pregnancy" that seemed to be based on some annoying 80's notions of gender roles, wherein the woman gets all kooky and fat and frets about her wardrobe while the longsuffering husband must attend tedious birth prep classes and bring his wife jewellery after she gives birth.
The Mother of All Pregnancy Books has been a great source, especially when it came to calming down my occasional "is this normal?" freakouts. It is also useful at guiding you through the healthcare and benefits system unique to Canada.
Other friends really like the Sears pregnancy books. They are quite old, but from what I have skimmed, they are pretty thorough.
Finally, I do recommend signing up for the baby center weekly newsletters. It is a bit heavy on the advertising, but each week you get a "your baby this week" newsletter, detailing new changes. They also have this charming tendency to compare the fetus to fruit. "your baby is the size of cantelope". This week, however, they seemed to run out of large enough fruit and switched to sports analogies. I was told my uterus is the size of a soccer ball.