Importing songs from folder, ignoring existing ones I recently rebuilt my iTunes library by creating a new one, and simply dragging &amp; dropping my "Music" folder (with about 1,000 MP3s etc.) into it.

The folder that contains the music files is organized in sub-folders by artist, and then sub-folders by album.

However, the import process seems to have been incomplete: many songs and even directories are missing, i.e. they are present in the physical folder, but not in the iTunes library.

Is there a way add the missing files from the folder, while ignoring the items that are already in the library?

I have done extensive re-tagging and renaming in the iTunes library since the import, so just starting from scratch (deleting the library and fetching everything into iTunes again) would be a very painful option.
If you have to start over, and you might, http://www.tuneupmedia.com/ might be worthwhile to avoid retagging your whole collection.  Good luck.