I am so sorry to hear what happened. I feel awful for you because I know if it were my daughter I would feel as crushed as she would. I once had to call Downtown Disney about an item I wanted to buy (because I didn't decide I wanted it until we returned from our trip a few days later) & the people I spoke with were so very helpful. They hunted through the store to find the item I was describing, charged it to my credit card, & sent it right to me within the week. They were very kind & helpful. I bet if you called a shop in MK they would send you an autograph book but of course you'd need some signatures...maybe someone there would get you a few. Well, that's my idea. Hope it doesn't seem too silly...it's the only thing I can think of.
Since your daughter was having a birthday party, do you think maybe the book got lost with all the wrapping paper trash?