I just picked up a copy of Steve Tarani's new book on karambits at a local Borders book store. Many of the techniques are applicable to defensive use of hawkbill or billhook-type knives such as the Civilian, Matriarch, and Harpy. The title is "Karambit" published by Unique Publications, and I paid $16.95. If Borders has it, then I would guess all the major booksellers can get it. I knew Steve Tarani made good, easy-to-understand videos, and his book is very readable and the photo sequences easy to follow and understand, IMHO. Before anyone jumps in and says a Civi or Harpy is not a kerambit/karambit, some of the karambits shown in the book do not have the finger loop, and like I said, SOME of the techniques are applicable, not all.