What are the most effective free or near-free marketing strategies for self-published books?

Douglas R Pitts
author of "144 Aphorisms"

Doug, the link below has some great recommendations from someone who has been doing the work for a while. I found her suggestions about Goodreads to be especially helpful and have done a book give away both there and at Librarything. My profile on Goodreads also earned me a radio interview request, so it is an especially promising site to become active on. Good luck!

http://olgasdaughtersblog.wordpress.com/

Thank you. That is helpful information.

Glad to be of service. If I could be so bold, another suggestion might be to flesh out your profile here and at other sites where you want to establish a presence. A professional looking headshot and a few words about your book/link to it on amazon may be enough to encourage a reader to find out more about your writing and maybe even purchase a copy. Investing a few minutes can really raise the interest level of others in what you have to say. Great cover, by the way. Stacey

Thanks Stacey. Continue to be bold.

Getting testimonials!!!! Asking influencers, fellow authors, or professors for testimonials is free and builds up trust with your target audience.
But before reaching out to people and asking for a testimonial you need to know who your target reader is. Because you want to reach out to people that your target reader respects and follows.

Here is a great article on how to find and attract your target reader: http://www.talkplustell.com/blog/

I'm a great supporter of Goodreads too. I also interview a guest author each week on my website www.ritaleechapman.com. Interviews by other authors is another useful tool. If you are interested you can contact me through the website.

Lots of good information in this thread. As a fellow writer, this is much appreciated.

Use social media. Share snippets, behind-the-scenes content, and personal stories related to your writing process to build a connection with potential readers.

Also, use book review blogs and websites. Reach out to bloggers who review books in your genre and offer them a free copy in exchange for an honest review. Positive reviews can significantly boost your book's visibility and credibility.

Not free, but digital billboards can be pretty cheap. I've heard of authors promoting their work this way.
Did a bit of research and found https://seeblindspot.com/, a platform where you can place ads on digital billboards. They offer prices as low as $0.06 per play, which is quite reasonable, I'd say.