I highly recommend this book - Publish Your Patterns by Nancy Restuccia/McKenna Linn.
http://www.amazon.com/Publish-Your-P...ublish+pattern I was in your position a few years ago, when I found a quilt that I really liked on an Amish web site, but I couldn't find a pattern for it. Then I found a similar quilt in a book of best quilts of the 20th century, but I still couldn't find a pattern. I determined that the basic design was in the public domain. So I "figured it out" and made a quilt, displayed it on this board, and got so many requests for the pattern that I wrote one, got volunteers to test it, refined the methods to be easier based on their feedback, and sold the pattern through this board and elsewhere. (My avatar quilt is from my pattern.) Good luck!