Wow ! You really got some great ones.
For 10 cents each, you did good if you resisted taking them all.
I originally had not used books, but when I decided there was some new stuff I'd want to try before too long, I now always look through them at the Goodwill or other thrift shops. I got some general things like old dictionaries, word finds, things with schematics and other interesting illustrations, mostly just to make collage papers that would have something interesting peaking through... THEN I got into other types of books, decorating, art and the such. It was fun trying to decide what I might or might not use and to see old books in a different way.
On youtube there is a Dutch collage/mixed media artist and one of her journals is an old cook book. She glues two pages together so it will be thicker and then paints and/or collages in it. She did cover the binding in collage too.
RE: Someone dropped off some great stuff at the library in used books. 10 cents each