Seth Godin's blog is very inspirational. Sometimes it doesn't tell you how to go about doing something. Seth leaves that up to you. He motivates you and stimulates your thinking.

Seth has some great "big picture" ideas - he is someone who I trust to see one level beyond what most people are thinking. He also turned me on to the idea of a "permission asset" which really changed my approach to building my business. I've enjoyed most of his books that I've read.