Originally Posted by taming
Recently someone wrote that when they requested a preview of their "lost" book the complete book was downloaded. It might be worth a try.
That may have been me. I deleted a gifted book from my touch and then with the sync was gone from my account online. Not in purchases (since it was a gift and I didn't purchase it) or trash. Requested a preview and got the whole book. One clue I had that it might work is that when I went to look at the book I clicked on "buy now" but wasn't given the option to buy it only download the Adobe ePub. If you see the same thing I'd be willing to bet the preview trick will work for you.