TuneRanger
www.acertant.com/web/tuneranger/default.htm
From the page
Saved with the link. Notes from 2007 to 2016 are mostly the page's own words, so this is probably an excerpt.
Chances are you keep your iTunes music and video collection on more than one computer, so you already know how hard it is to keep them all the same. Add a spouse and some kids to the mix and the task is virtually impossible - until now.