The book by Ormond McGill to get is "The New Encyclopedia of Stage Hypnotism". This massive tome, published in 1996 by Anglo-American Books (based in Wales) is the one indispensible work for any person interested in stage hypnosis (and in fact many people use its techniques for hypnotherapy, lectures on hypnosis and so on). The "New Encyclopedia" contains all the material which was contained in Ormond's earlier, shorter books and manuscripts on stage hypnosis, and supersedes them. (The earlier works, such as "Professional Stage Hypnotism" and the original "Encyclopedia of Stage Hypnotism" are still worth reading, but the "Nw Encyclopedia" is both more comprehensive and better-written, as Ormond's writing style has greatly improved over the years, if I may be permitted such a comment on such a distinguished figure.)
The other really excellent book on stage hypnosis which no-one interested in the subject should be without is Jerry Valley's "Inside Secrets opf Professional Stage Hypnosis", which is published by the National Guild of Hypnotists (New Hamshire, USA). It's an extremely useful and straightforward manual in which the author gives his induction and the entire repertoire of routines for three separate shows. Also Jerry gives a lot of good technical information regarding sound, lighting and so on, and tips on showmanship, derived from performing in the real world for over 30 years.
Quite frankly, once you have these two books, none of the other manuscripts, pamphlets, videos on stage hypnosis that I have seen remotely come up to the same standard.