The greatest boxing book I ever read was George Plimpton's Shadowbox. I can't even begin to describe all the great boxing stories and tidbits inside there. It details a lot of Ali's biggest fights before, after and behind the scenes. He goes in great detail about guys like John L Sullivan and various other memorable (and not so memorable) fighters from the late 1800's/early 1900s. Also a lot about Ernest Hemmingway's obsession with boxing. SImply bput if you are a boxing fan get this book.