Enemy at the Gates: The Battle for Stalingrad by William Craig is a great book on the battle for stalingrad. It is a book of 5 years of research the author did on the battle, reading reports from the germans, russians, and everyone else involved. He also interviewed people that fought in the battle on both sides. The book reads somewhat like a novel, but gives the straight facts right out. It follows key players in the battle and other foot soldiers that were just basicaly grunts.
Here is the link to the amazon.com page selling it.
It was the base of the movie Enemy at the Gates.