Michael Neufeld has a couple of books concerning Von Braun, a biography called Von Braun: Dreamer of Space, Engineer of War and The Rocket and the Reich: Peenemunde and the Coming of the Ballistic Missile Era. Both have been recommended to me by Cold War historians, though I haven't had a chance to read them myself. I asked for the recommendations because I wanted something that didn't waffle about Von Braun's Nazi career.