I can second the "Slip Joints My Way" book by Don. Here's a pretty great tutorial,
http://www.americanbladesmith.com/ip...project-knife/. Also check out the one posted by Steve Culver at culverart.com. I've made several of my own templates using free software called inkscape. It allows you to rotate the blade around a specified point to see if everything fits. I posted one of them here for peer review. I'm happy to say I used it to successfully make two functioning slippies.