TrackSift brings together 9 easy to use tools for iTunes to assist with creating special playlists and cleaning up your iTunes library.
9 Tools to clean up your iTunes Library.
Delete "dead" tracks, delete empty playlists, and delete unwanted Genre names
Find songs without album art, without lyrics, and not in playlists
Create "One-Hit Wonder", "Two-Fer", and "Three-Fer" playlists