I went to Vegas about 2 months ago and saw hypnotist, Marc Savard. It was one of the best, most entertaining shows I have ever seen and I highly recommend it. My parents saw the show a few weeks later and loved it as much as I did. If I remember correctly, tickets were no more than $25 each.
Here's some info
Marc Savard Las Vegas
You buy your tickets at any of the tix4tonight stands on the strip.