We have several public libraries close enough that my daughter-units can bike easily enough to most of them. I've donated books to each over the years and it's not that they don't have an over-supply from willing patrons. It's the resources to bind them for shelving and use, catalog them, and then put them out so they get used.
Tangential thought: I watched one mom put a book back because it was "old and a hard-back" (I asked because I knew the book was a good read.) It didn't have a cover sexy enough to hold her daughter's attention. Gahdferbid the story do that...
If your local library has volunteer hours, find out what you can do to assist them in getting their back-logged books out on the shelves. If it's like our system, you'll have to go through _some_ training but once you're in you can make a difference.
The Ranger