I love making ATCs and now I love my new found art thingy called Zentangle. While it can be overwhelming searching through all of the books and sites that have Zentangle patterns; it is non-the-less a fun and rewarding journey. I have all three of the Zentangle books by Suzanne McNeill and Sandy Steen Bartholomew and have them 3-hole punched in a binder. Along with the three books I also have tons of printed out sheets of paper with the patterns I have been collecting from other wonderful and inspiring Zentangle artists.
You can find all of the books with a Search of Amazon.com for zentangle! Here is the Zentangle Basics book with a link to get started.
Here are 2 of the stencil Zentangles I did this weekend: