Recently read 'Racing Through the Dark' by Scottish cyclist David Millar and 'The Psychopath Test' by John Ronson. Both worth a read.
Millar's book is the best first-hand insight I've seen revealing the extent of drugs use in the Tour de France, the whole culture seems/seemed geared towards cheating. The latter is an easy read and interesting even for someone like myself as a complete layman on the subject.