After having editted some existing themes to my likings, I want to try to create a WordPress theme from scratch. I already bought the ebook "How to be a WordPress Rockstar" a couple of months ago , which I have taken a look in really quickly. It looked promising, but the book was written in 2008, and I'm afraid that it is a bit outdated by now.
Do you think the same? Or can you suggest me other sources to learn to theme from scratch in WordPress?