I was manually backing up my iPhoto collection to CD-Rs the other day. My iPhoto library was larger than one CD, so I took some of the folders out of the library. Unfortunately, I then opened up iPhoto. Since the photos weren't in the right spot, iPhoto must have deleted the references to them from its internal database.
Anyway, I still have the "2002" folder (which contains all the pictures) intact, but I think maybe the Library.data file or Dir.data file needs to be rebuilt.
Has anyone had any luck fixing a problem like this? Any help is greatly appreciated, as I have ~700 photos in this album that I really don't want to have to manually go through and edit all over again...