Novels and Children's books in English

Hi. We live in the Reus area, and have a lot of paperback novels for adults, and children's books (kids have now grown up) in really good condition. It seems a shame to throw them out, when other's might wish to read them. We once visited a shop in Castellon that bought and sold second hand books in English. Does anyone know of any such shop in this area, or have any ideas? Thanks. Bern & Jean