My doctor is the medical director for the american asperger's association. He is the one who has the hbot chamber and suggested that my daughter and I do it. It's supposed to help heal, well, about everything. There has been some research that it helps the negitive symptoms, like panic etc, meltdowns.. when it comes to autism. I don't want to change who I am, but heck, if this works, I'd be happy not to have panic attacks, and I want my daughter not to have to suffer with meltdowns for one. My psychiatrist's LJ page is aspieone and his community is http://community.livejournal.com/aspergersassoc/profile
There is more info on the site. So to answer your question, a neuropsychiatrist in your area should have one, or know a hospital that does. I don't think it's covered by insurance yet...depends on where you live.