That's a great site! One of the primary contributors is a guy name Dino LaBiste... he's a park ranger and expert naturalist for the East Bay Regional Parks district here in Nor-Cal. I've taken several classes from him through EBRP, on cordage, outdoor survival, fire-making (about three times now actually), and flint-knapping. He's a great guy; extremely knowledgeable and very helpful and participatory in his teaching style. His classes through EBRP aren't very expensive at all, and sometimes are even free. I've learned a tremendous amount from him in the last couple of years.