But you remember which folder directory it was in right? So you could re-add it. Then try deleting.
Alternative: Showing Hidden files & folders:
Search - VersionTracker Mac 4 Ever : Le bit de l'invisibilité
Below I have attached the
InVisibles utility I used on my G4 with OSX 10.4 & earlier (you may wish to get a later version). If you run the utility once it makes all hidden files visible, run it again & it hides those that had their visibility changed. This will allow you to deal with the files & folders in question.
Above I listed alternate programs at Version Tracker that do similar kind of thing. I have no idea how good they are.