FreeReadFeed is a great place to find free books. The site is robust, allowing you many options to limit your search. Or you can drink from the fire hose and look at everything that is free.
I sort by Most Reviews (then (sic) stars) so I’m only looking at the books that have had many eyes on them. Every day there are pages of freebies so you will surely find a gem or two.
HarperCollins issues a daily email called BookPerk which features their bargain books. When you go to Harpercollins.com, there is a slim banner about signing up for BookPerk (right below the Covid-19 announcement). The expiration date of the price was recently added.
BookBub is a quality site that has a large pocketbook. You can read more about it here.
The site sends a daily email based on your preferences. BookBub has a blog and sends emails with recommendations. It is a very well-done site.
I have not received consideration to tell you about these sites.
 
Kindle Daily Deal Link
Audible Daily Deal Link (scroll down the page)
Daily Gold Box Deal Link
 
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