How would I go about getting a book appraised?
The library cannot perform appraisals, but the American Library Association's Rare Books and Manuscripts Section offers these suggestions:
Many booksellers perform appraisals as part of their business. The Antiquarian Booksellers’ Association of America has a membership directory on its Web site (http://www.abaa.org) that allows you to search for qualified booksellers by geographical region or by their fields of specialty. Your local yellow pages directory may also contain the names of “used,” “rare,” or “antiquarian” booksellers in your area. Because the range of rare books is vast, you should seek an appraiser who is knowledgeable about the particular type of books you have. Ask for references and referrals until you are satisfied that you have found the right person. Other sources for finding appraisers include the Appraisers Association of America and the International Society of Appraisers.