I've been 'zentangling' for a number of years- and have incorporated the process in numerous quilts- there are now books available at Joanne's and other craft/hobby shops with actual zentangle patterns. the last time I stopped into joannes there was a quilting workbook too...I've not purchased any of these books- but I did thumb through them- once you start 'tangling' you do not need a book---unless you really need 'strings' to get you started. I have been encouraging all of the 'children' in my family to try it out when they are feeling...down, bored--a couple of them have really taken to it
for me it is as 'zen' working on a quilt as it is working on tiles- I've even been drawing on 3" fabric tiles to some day put together into a whole quilt