I thought I would provide an update, since we arrived home on Wednesday night.
All the parks had autograph books, and had I checked the airport when we landed I would have found them there too. UO had about 4 versions, some with specific individual characters like Shrek, Spiderman, etc. and some with the UO/IoA logos. We did not buy any, I decided to give her stickers from all the characters we would be meeting (UO, Busch Gardens, Disney) to decorate one of the books we had purchased here at home, even Disney, so this trip is all in one book.