Troy posted for a while on
www.driveonwood.com
It is the go to
online gasification site to check out. Through there you can order Wayne Keith's book; one of the best there is on gasifiers for mobile applications. Also there are research papers and book pdfs as well as links to other sites and books. (Edit Troy does mention them in his presentation) from personal
experience I would suggest you stay away from the fema listed above as it's a known engine killer. There is nothing wrong with the old books listed but check out what people are building now using materials and techniques from today first.
Cheers, David Baillie