According to this 1959 US Embassy document, it costs Rs.500 for a Yeti search expedition permit. You are allowed to photograph or capture a Yeti, but you are not allowed to kill one or shoot it "except in an emergency arising out of self-defense."
Mark Frauenfelder is the founder of Boing Boing and the editor-in-chief of MAKE and Cool Tools. Twitter: @frauenfelder. Come and hear Mark speak at the ALA conference in Chicago on July 1.