I shopped for books once, and got a book shipped from Goodwill.
So, I donated a bunch of books there, hoping that someone who REALLY wanted one would get it online, for example, through Amazon (which I almost entirely avoid)
They operate an online store shopgoodwill.com but it's an auction site, and I detest auctions, since they are often "gamed"
The more expensive and fancy items go there. I never bid there, but it's a great place to snag photos of rare items.
I don't donate to libraries because they have limited space, and once a year, sell books, the remainder going to the landfill, which I really detest.
FWIW, old books can be found online for free.
You didn't see this, but if you fake an autograph, the book might drag in more money for charity.
Books that make it to the thrift stores will bring in maybe a quarter.
Anecdotally,
I have hundreds of pounds of books of great interest that I paid for, such as woodworking and landscaping, for which I found PDF's, ahead of move plans. My "BEST" solution is to donate to, or create "Little Libraries" and I will pursue this even if people don't return my emails. I can even build them.
See if there are any in your area, and donate.
https://littlefreelibrary.org/
SAY! I am going to pursue this. It's a great idea.
Go Warriors!