This is interesting. I am planning to start doing consulting into the analytics industry and started a blog 6 months ago. So far, just by adding a "free call" page and writing few blog posts, I got a couple of leads. It's not much, but it's encouraging. I am now in the process of writing an ebook which I will sell for $100 or so and see what happens there. I do plan to test online ads for the ebook. The idea would be to use the ebook to build a customer base for consulting, let's see. Writing an ebook it's not easy, but it is helping me a lot to better understand my potential customers and define my consulting product a bit more.