It's actually alot easier than you think it is. I have done a little hypnosis (practice on myself), and it's actually kind of fun. There was a setof books reccomended to me once but I forgot the name and will need to relocate it. Basically, hypnosis is just a really deep state of relaxation where you happpen to be aware to everything thing around you (it's called hyperawareness, one of the really scientific terms out there

). At that point, your mind is very succeptable to suggestion and will follow whatever suggestion it is told unless you disagree to it (like if someone told you to strip naked in Times Square under hypnosis, you wouldn't and would pull out of hypnosis quite quickly).
There's not much to be skeptical about, just be aware it's not the all powerful tool it's thought to be. If you've seen Office Space, that's close to what it's like (except the hypnotist doesn't usually die in the middle of the session

). Now when people start talking about regression and psychics...then be skeptical (I know I am).
I'll look through Amazon for that book...