There is one project[0] that accomplishes the same thing, but instead of searching for the titles, it searches for the links to online stores (like Amazon) and then checks if the links are indeed books or not. Might be relevant to you.
I really enjoy the service. Mostly go through all the top books and see if anything calls out to me, and so far the site has done really well at keeping the informal contract of "I give you my email, you don't spam me".
The exception will be items from sellers of products not available on Amazon. And there may be some communities in Reddit that are more loyal to another e-commerce platform or site you would miss (crafters to Etsy, antique collectors to eBay, etc.)