If you are looking for esoteric library books and in California, try Link+. It lets you get books from many libraries, including university libraries. My tastes

If you are looking for esoteric library books and in California, try Link+. It lets you get books from many libraries, including university libraries. My tastes are very, very obscure but Link+ often finds the 1953 computer book that I'm looking for. (Other areas may have similar inter-library loan services.) https://csul.iii.com/ https://csul.iii.com/