Characters will sign just about anything, so long as you aren't wearing it.

“It doesn’t have to be an autograph book. Characters can sign shirts, posters, postcards, whatever your imagination can come up with.”

So maybe another autograph book just makes everyone yawn. The characters in the World are perfectly capable of signing whatever you can think of. Want a shirt covered in autographs? How about a poster of the princesses signed by the princesses? Just about anything can be made into a wonderful keepsake with the right autographs. Heck, a postcard signed by Mickey makes a great pick-me-up for those who you left at home. Or maybe an easy way to remind them that you’re having the time of your life!