A great book outlining (in great detail) a powerful theoretical defense of abortion is David Boonin’s A Defense of Abortion. It covers all the arguments I’ve mentioned here, and goes greater into depth on many others.
We Remember is a classic of pro-choice feminist literature that anyone interested in the history of women’s reproductive rights should read.
I follow Ann Hibner Koblitz’ wonderful blog, where she discusses abortion and contraception related topics.
For wider coverage of feminist topics, I also recommend Meghan Murphy’s excellent site Feminist Current.
Defending Feminism 