John Piper, Lincoln's Logic on Slavery Applied to Abortion
R.C. Sproul, Video series on abortion (streamed on the web for free)
Robert P. George, Our Struggle for the Soul of Our Nation
Ed Whelan, Senate Testimony on Roe v. Wade (2005)
Michael New, The Case for Pro-Life Optimism
Star Parker and Gary Bauer, A Dream Unfulfilled: Roe v. Wade has Played a Big Role in the Devastation of the African-American Community.
You may also want to check out these two later posts:
Abortion and the Early Church
Abortion and Obama's First Few Days
May God bring an awakening to this country that will bring with it the will to end abortion!