Okay this is link inception @GMan , but the first one is a link to a post that has a link to the KNF book for free, and the second one will take you to a post with a link to the JADAM book (written by the original guy’s son).
They aren’t brilliantly written, but the concepts and recipes are all there for you explore. It’s a great jumping off point.
JADAM in particular is ultra cheap and easy, and doesn’t require all the sugar/ molasses/jars you need for KNF