This site highlights the Palaung People of China, Myanmar and Thailand. Good information and some nice photos. Check it out at: http://forgottenpeoples.shutterfly.com/
This site mentions Matthew Ellison, has a book review, Bruchko by Bruce Olson. Check it out here: http://takeyourvitaminz.blogspot.com/2006/10/1615org-bruchko.html