iTunes deleted my Audible books from my iPod

iTunes' authorization obsession has gotten out of control again. It's deleted all of my Audible.com audio books from my iPod saying that the device isn't authorized.

I'm minding my own business the other day when iTunes decides that my laptop is no longer an authorized device. When I try to re-authorize it I'm told that I've already used all five of my authorizations (I don't know how it figures that... I only have two computers). The only option I can find is to de-authorize all devices. So I do that, figuring that I'll just re-authorize my two computers and get rid of what ever the other three mysterious authorizations are. Easy enough. Except the next time I connect my iPod it removes all of my Audible.com audio books, plus another 1,500 or so other files, mostly photographs.

These are all files that I either purchased or created, and iTunes refuses to let me access them. I can't find anything that will tell me how to correct this. Can anyone help me figure out how to make iTunes put my files back onto my iPod?