Get Out There and find new ways of Advertising.
Another Great Way of advertising is writing an article about what your book is about and then add a little bit about the book in there. Tom Carsley is a great example. He's gotten his article on this great survival blog and he's created some buzz.
Digital Advertising is the best direction for Digital bound books. Project Wonderful is an advertising site every small digital business should use.
The First in a long series of DIY family books, the series "Daddy, What are you making now?" is currently available on Kindle.