I wish I could accept books to sign and return — I used to, but came to the realization I was spending 4-5 hours a day dealing with snail mail requests and signed books, and that it was actually starting to prevent me from writing. So I made an arrangement with Books of Wonder, an independent New York City bookstore — I make sure they always have signed copies of my books on hand, and you can order any or all of the books by calling the store at (212) 989-3270. [You can ‘t order the books off their website. You MUST CALL them.] They have signed hardbacks, paperbacks, box sets, etc, and will ship anywhere.
I do get requests for “autographs” sometimes, but autographs aren’t really something writers do. That’s why signed books are meant to be something special. Scrawling a signature on a piece of paper feels silly in a “Why would anyone want that?” way, and again, it’s a matter of time and the cost of postage, both of which prohibit me from being able to send out signatures. (Again, signed bookplates are only available to schools and charities — not to individuals.)