Sigh. I've had to explain this before, and yet it never gets any less absurd.
A production error resulted in the wrong ISBN code being linked to Reap the Whirlwind at some point along the way (I'm not sure if the number was wrong on the cover or in the Simon & Schuster database, or both.) The result is that it was impossible for retailers to order new copies of the book, which is ridiculous, because its sales were very good (or so I was told).
I was told that the problem was fixed last summer, and for a very brief time the book was back in stock on Amazon, B&N, etc. Then the same problem recurred, and the print edition is once again conspicuous by its absence. And because of the numerous economically motivated layoffs at S&S since December 2008, there is no one left who who has either the will or the knowledge to fix it.
If you think this is frustrating for you, the readers, imagine how I feel right now...