When you're done with the ebook(.pdf) look into creating a .kml version too if possible, Google loves showing results for varied types of content besides plain text html.
Article directories, feed directories, new/throwaway blogs, new/low trust social profiles etc are all next to useless in providing value for your site now. Look at it this way - if anyone can get a link there Google will not place much value in it. I'm also seeing that you need to have a link on any given page from the moment it is published to get full benefits so finding high ranking pages isn't as useful anymore either.
Plant your seeds and tend to your field, it will grow in time.