Here are my ideas for building your internet presence without spamming people, tweeting daily or building a Facebook page. I call this organic growth. All it takes is time.
1) Become part of the communities that are interested in your genre - for me, travel sites, retirement sites, boomer sites - for others it can be cooking sites, business sites, dog sites, parenting, etc. - start participating in the discussions a couple times a month. Always add to the discussion with interesting material and include a link to an article you wrote, or a link to your website, etc.
2) Respond to blog articles in your topic area (set Google Alerts so you are notified when your "key words" appear in a story) - again offer your information or opinion in their comment section or directly to the blogger, and links to your site.
3) Ask bloggers in your genre to review your book - send them a review copy and follow-up to make sure your story gets posted.
4) Use Google Alerts to follow news stories in your genre. Use those journalists names/emails to build your media list so that when you do a news release, you have your own list to send to with the hope that they will be interested in your PR and follow-up with you to do a story.
5) When you find a news story in your genre in a newspaper or magazine, go to the comments section and comment on the story, add information from your perspective and leave your contact information including your website.
6) Trade links and stories with complimentary websites and blogs - build a relationship with others in your genre - help each other out with ideas.
7) Write articles about your topic and submit to sites such as ArticleCity.com and Ezinearticles.com - other bloggers and websites go to places like this for content to post. The ‘quid pro quo" is that they keep your bio at the bottom in tact (with your website address) and keep you as the author. I find articles all the time that I wrote years ago that are still being picked up. One just yesterday that I wrote in 2007!
I have been doing this now for 6 years and have a presence on thousands of places on the web. All of these tactics will also improve your page ranking/SEO of your website. I just Googled my "book title" (always in "quotes") - and it says there are 6,100 places on the web that have my title associated with them. No advertising has been done - all organic growth. All without costing me a dime - except my time.