Neuro-Linguistic Programming

Using Your Brain for a Change Richard Bandler Probably the most accessable book on NLP, and the one I always recommend as a first NLP book.
 
Time for a Change Richard Bandler Carries on where 'Using your brain for a change' finished off.
 
Transformations Richard Bandler
John Grinder
A brilliant book covering hypnosis and NLP. This was the first book that interested me in hypnosis. A must read.
 
The New Encyclopedia of Stage Hypnosis Ormond McGill A massive book about one of the current hot topics. Especially useful if you want to learn how to hypnotise a chicken or a lobster!
 
Unlimited Power Antony Robbins Not strictly an NLP book, but a more holistic approach to improving your life.
 
Training Trances John Overdurf
Julie Silverthorn
A brilliant book on using trance states in a training environment.