Book appraisal services are not offered by the Stanford University Libraries, but staff members offer the following suggestions for getting the valuation of old books on your own:

• If you are in the San Francisco Bay area, here is a resource that our staff uses: The Brick Row Book Shop. The Brick Row Book Shop offers appraisal services of books, manuscripts and archives for numerous purposes: donation to educational institutions, replacement value for insurance coverage, division of property, establishment of a fair market value for sale, etc. There is a link on their site for Appraisals
• You can try this public site: AbeBooks.com. This Web site is an online marketplace for old books.
• Or you can show it to a book dealer. Any major yellow pages will list Books, Used & Rare.
• There are also a couple of good, general sites for analyzing the value of books. Bookride is an amusing site with lots of advice and links. ViaLibri has a search engine for checking about 20,000 book dealers worldwide.