If you're vaguely aware of the rules of baseball (or, if you're a fan - basicall anyone except a total beginner on the sport) I've just finished and can heartily promote Summer of 49 by David Halberstam. As a lesson in the first rule of great non-fiction it's ideal - do a tonne of interviews. And then another tonne. And then another. The me-me-me masturbatory vibe of the modern blogosphere, combined with inherent shyness that we all have to overcome, can obscure that rule, but it's priceless. If you don't do the interviews, you'll end upwriting about yourself - a subject about which nobody cares.