Hypnosis has indeed been shown to be able to have significant effect on bone growth (although not in the context of growing taller, but in the context of helping broken bones heal much faster). Here is the study from Harvard Medical School:
Harvard Gazette: Hypnosis helps healing
The same article also talks about hypnosis has been shown to accelerate the healing of surgical wounds (post-operation). So clearly hypnosis can cause physical change in its subjects.
Also very famous are the "hypnotic blisters" cases. The hypnotised person is told that he is going to be burned with a very hot object. The hypnotist then touches the hypnotised person with a room-temperature object. Nevertheless, the hypnotised person immediately develops a blister where he has been touched, as if he had really been burned.
http://www.psychosomaticmedicine.org...t/25/3/233.pdf
My final thoughts:
I don't want to sound discouraging. I do think that it may well be possible to use hypnosis to induce the body to grow taller. On the other hand, I suspect that this isn't really going to be worth the time & effort, unless you really need the height for some significant reason - eg you are a competitive basketball player or something.
If you just want to grow a little taller because you think you look better if you're a little taller, I would suggest instead that you consider using hypnosis to alter your self-image (ie make yourself happy with your height as it is).