'Apollo', Charles Murray and Catherine Cox [0] is a terrific book about the engineering and project management of the Apollo program. They don't talk about the software much (if anyone has a suggestion, I'd like to hear it), but there are a ton of great back stories about the technology, planning, and management of the program that led to July 20, 1969.

[0] https://www.amazon.com/Apollo-Charles-Murray/dp/0976000806

I second that recommendation. The book can be found for cheap, plus there's even a kindle version if you prefer that format:

http://www.amazon.com/Apollo-Charles-Murray/dp/0976000806/