Right now when using "Locate..." on a missing file, it opens the official Library folder, regardless of where the file actually was. How about opening the parent folder of the missing file, instead? I mean, if the whole folder it was in is missing then back up to the nearest existing folder.
[Edit] Curious, now I've seen some behave that way. So I guess the question is why others don't. They may have all been in the inbox, come to think of it.