Derrick Jensen's new book, Thought to Exist in the Wild: Awakening from the Nightmare of Zoos can now be purchased from him in both hardcover and softcover. If you want to purchase them from Amazon.com it looks like you'll be waiting until June 15th.
I got the chance to read Thought to Exist in the Wild through Derrick's Reading Club. It is well worth the read. I highly recommend it, like the rest of Derrick's work.