Fortunately, there are plenty of places for you to promote your book for free. Hundreds of online reviewers are happy to receive a book in exchange for an honest review, and many post their reviews on multiple platforms. There are also numerous sites that publish interviews with authors, as well as places to post your cover reveal and excerpts.
The resources below will help you on your way to effective marketing and promotion. I suggest that before you begin promoting your book, you look at these lists and sites and make a list of your own of the various types of promotion you'd like to do, and then find the sites that provide what you are looking for. Keep careful track of where you have promoted your book, and don't forget to evaluate the results!
Note: For all of my articles on self-publishing, including resources for promoting your book, marketing, getting reviews, setting up your author website and more see: Self-Publishing
___________________
List of lists
Indies Unlimited has the longest, most comprehensive list of places to promote your book that I have ever seen.
Digital Pubbing's list of 110 tools to find readers and reviewers is conveniently broken down into categories (reviews, advertising, interviews, etc.) to help writers hone in to the type of promotion they are looking for.
Kindlepreneur lists 127 places to promote your book, free and paid.
Great Sites That Offer Indie Book Reviews discusses top places for book promotion - free and paid.
Self Publishing has a huge list of 100 places to promote your book (both free and paid).
Build Book Buzz's handout is a substantial collection of resources that will help you find media outlets, reader review sites, and online review sites for your book.
Angie's Diary lists the top ten free promotion sites for self-published books.
Savvy Writers has a list of 46 free promotional sites for self-published books.
Individual promotional sites
Authors Den allows self-publishers to download sample chapters which readers can review. You must have a book cover before you can upload a chapter. Detailed instructions are on the site.
YA Books Central offers book reviews, cover reveals, author profiles and interviews, sponsors giveaways and contests, and accepts advertising for YA books.
Book Buzzr offers paid promotion, but you can try it for free for 14 days
Books on the Knob offers free reviews, will post your giveaway, discounted books,
Indie Books Blog is a blog that promotes self-published books. Fill out the form to have your book posted, and tweeted.
Book Life, run by Publishers Weekly, lets you submit your book for review, register your book, and post an author profile, Don't forget to connect your social media accounts to your profile!
Story Cartel offers readers free e-books in exchange for honest book reviews. Readers are given thirty days to read the book. If, by the end of that time, they’re able to send a link to their posted review back to Story Cartel, they will be entered in a drawing for either five print copies of the book, three $10 Amazon gift cards, or a Kindle (as supplied by the book’s author).
Indie Book Reviewer lists book review sites and blogs by genre: Science Fiction & Fantasy, Comedy, Historical, Horror, Inspirational, Mystery & Thriller, Romance, and Nonfiction. Some of these may be temporarily closed to submissions.
Indies Unlimited offers an array of free features includes Thrifty Thursdays, Print Book Paradise, Kindle Unlimited Hump Days, and a weekly flash fiction challenge. The submissions guidelines are explained in detail on the features’ respective pages.
Forums
Book Talk hosts free forums where authors and publishers can post their books. Book Talk also offers paid promotion.
Online Book Club is a forum for readers and authors. Reviews are also offered - both free and paid.
Amazon’s Meet Our Authors Forum
Kindle Boards
Mobile Read
Nook Boards
Additional resources
For more free publicity sites see: Free Publicity for Your KDP Select Free Days
And for reviewers who accept self-published books see my List of 427 Online Reviewers Who Accept Self-Published Books