I would drop by and ask to speak to the manager or an assistant manager. Frequently, bookstores be happy to stock a few copies of a local author's book in their local section. Some will even host a reading or signing.
Bring some info about your book--anything from a one-page flyer to a promo packet including postcards, bookmarks, a bio sheet, etc. Make sure you include the ISBN and information on how to order the book. They're unlikely to get it from Amazon, though, so find out which distributors your publisher uses and include that. If they don't have a distributor, or have one but it's not one the bookstore deals with, provide the publisher's contact info. If you don't already know it, it would help to know what the usual terms are under which your publisher sells to bookstores (discount, return policy).
Or if you can get them at a favorable enough rate yourself, some bookstores will buy directly from the author.
Best of luck with it!