J.K. Rowling’s Harry Potter books have finally become available for e-readers, in a unique business arrangement that has cast a spell over Amazon and other digital retailers.

Amazon today sent out a press release that it now has all seven best-sellers for sale in digital form. This was surprising in light of Rowling’s previously announced deal with Google that called for the titles to be sold exclusively through Rowling’s website and e-book shop Pottermore.

It turns out that has signed a third-party distribution agreement with Pottermore rather than disappoint its customers, a first for Amazon and a solid demonstration of the hold the Harry Potter books have over the entire publishing industry.

Even so, clicking on Amazon’s “Buy at Pottermore” button takes customers to the Pottermore Shop, where buyers are required to set up a separate account with its own password. Once that’s taken care of, the purchase is straigntforward and the books get delivered directly to the user’s Kindle or other e-reader in .epub format, the open e-book standard from the International Digital Publishing Forum (IDPF).

That means fans aren’t limited to using a Kindle, of course. Any e-reader will work, including Barnes & Noble‘s Nook, Sony Reader, Kobo, and tablet. All seven Harry Potter books are available, so far only in English with other languages promised in the near future. The eBook versions cost $7.99 each for the first three books in the series, $9.99 each for the remaining four, or $57.54 for the entire set. Pottermore purchases can only be made by credit card, and most major U.S. and U.K. credit cards are accepted, with the noticeable exception of American Express.

The rest of the Pottermore site is still in beta and closed to the public.

Russ Grandinetti, Amazon’s vice president of Kindle Content, issued a statement on the news: “For years our customers have loved reading Harry Potter books in print, and have made them the best-selling print book series on We’re excited that Harry Potter fans worldwide are now able to read J.K. Rowling’s fantastic books on their Kindles and free Kindle reading apps.”

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