Used Harry Potter books are boosting sales for the secondhand book market and helping small, used-book sellers profit from Pottermania, according to Abebooks.com, the an online marketplace for used, rare and out-of-print books.

"Sales for used copies of Harry Potter books rose 300% in June," said Marci Crossan, spokesperson for Abebooks. "Our booksellers tell us people want the whole series and are scooping up used copies online. Even the new book, "The Order of the Phoenix," is available used at Abebooks.com, as are rare signed editions, versions in Latin, Spanish, large print, and audiobook."

There are 3,889 used JK Rowling books on Abebooks.com, and signed first editions are selling for between $200 and $1.2 million. At $1.2 million, the most expensive Potter item is for a signed galley proof of "The Prisoner of Azkaban" (Cheviot Books, England). The cheapest Potter item is .45 for a paperback copy of "Harry Potter and the Chamber of Secrets" (Pyramid Books, New Jersey).

http://www.abebooks.com/docs/ReadingRoom/Spotlight/harryPotter.shtml