Translating light novels takes time, especially for small publishers. Up till now, Yen Press was only releasing two volumes of the original Spice and Wolf books a year, with the sixth volume planned for June 12, 2012. The company must have gotten some extra help, because they've announced that from now on, they would release three volumes a year.
Yen Press announced on Twitter that it had licensed volumes 7-9 of Spice and Wolf. By June 2013, all three light novels will be released. This is good for fans of the books, but even with three volumes a year, it's going to take a while for Yen Press to work their way up to the 17th and final novel.
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