Q. Can you appraise my old books and magazines?

Unfortunately, no. As librarians we are neither trained nor qualified to value antiques or collectible print items. Appraising antiques and collectibles is best left to the experts. 

Maloney's Antiques & Collecibles Directoy is a long-standing directory of appraisers, collectors, and dealers. It was once a print directory and some libraries have older copies. Now it appears to mostly be online, and it is a pay service: http://www.maloneysdirectory.com/

International Society of Appraisers has a searchable directory or appraisers: http://www.isa-appraisers.org/