Like other before, I'd also recommend Ormond Mcgill's "The New Encyclopedia of Stage Hypnotism". I'd add that Teppo Holmqvist's "Hypnotic Influence - A Master's Class in Experiential Trance" is my favorite hypnosis book of all time. I have read dozens, all the classics. Other than a few on Past Life Regression, they are the only ones' I'd consider essential. Couple them with with hundreds and hundreds of hours of practical application, and you'd be scratching the surface of what is possible with hypnosis. Good luck.