First, the artist who shot the mindbending footage in the previous post, below, is Anthony Feyer, who also did a series of paintings and photographs of the same subject matter. When I contacted Feyer in early 2008 inquiring about his footage, he told me that while he shot several hours of footage, his primary motivation was to have it as a reference for his painting, not to release it as any kind of documentary. He referred me to Karen Kramer's hour long film from 1977, "The Jolo Serpent Handlers."
Secondly, if you are interested in this subject, be sure to check out the Snake Oil Amazon page for the book, The Persecuted Prophets, which is the best thing I've ever seen on the subject. It's long out of print, but last I checked on Amazon, there were a couple of used copies at very reasonable prices, like under $20.
Third, be on the lookout for a documentary called Heaven Come Down which ran on the Sundance Channel a couple of years ago but has never been released on dvd. I thought it was very well done and certainly threw the viewer a couple of curve balls.