Bud, Sweat and Tees by Rich Beem is a good read, and I'll add my vote for Four Iron in the Sole.
Just got into e-books, and "No Hiding in the Open - A Journey in Professional Golf" by John Hoskison is well worth a couple of quid to download. A good insight to life on Tour, written in a humorous, easy to read style - I whizzed through it in a weekend, as I couldn't put it down!