I don't know if I've plugged it here before but Mr. Playboy by Steven Watts is an excellent, excellent biography of Hefner. I learned a huge amount from the book, it covers his whole life as well as the development of Playboy. As you may know from my mega-PB thread I'm pretty interested in the magazine, it's kind of a perfect storm of sex/social issues/fashion and style and consumerism/retrograde masculinity/American ideals... Fascinating stuff. There's a well-narrated audiobook of it as well.

https://www.youtube.com/watch?v=FuNGDhU0NdA