The book Principles of Bonsai Design by David De Groot is back at Stone Lantern in hardback cover. It was hard to find recently but is now available. I have this book and as far as I'm concerned it beats any other book on bonsai out there unless you're just looking for pictures of trees. This should be a prerequisite for any beginner starting out in bonsai, maybe we wouldn't see an over abundance of sticks in a pot and rather a more disciplined approach and much better pleasing to the eye trees.