How to find files in your iTunes Library & NOT in Your iTunes Music folder AND visa versa.

Question

Finding Files in iTunes Music folder that are not Listed in iTunes
Make  2 Smart Play Lists and 1 Static Playlist as follows:
1. Make a smart playlist called “All Files” with this rule: “Artist” is not “123456789″ (or any nonsense name that won’t be in your library).
2. Make a static playlist called “All Live Files”.
3. Make a smart playlist called “Missing Files” with these rules: Match all of the following rules, Playlist is “All Files”, Playlist is not “All Live Files”
Preform the following operations:
4. Select all the files from “All Files” and drag them into “All Live Files”. The dead files marked  ! will not copy over.
5. “Missing Files” will contain all of your dead files. Select all and delete (Option+Delete). Voila, a nice clean iTunes library.
I keep these three playlists in their own folder. Whenever I gather more than a couple dead tracks for whatever reason, I delete all the tracks in “All Live Files” and repeat steps 4 and 5.
Finding Files in iTunes Library Are Not Present in iTunes Music Folder
Search on ‘Net for an Applescript called “Music Folder Files Not Added.” This will be at a site called Doug’s Applescripts and costs a mere $1.99. Install and follow instructions. This script also happens of clean up gremlins such as Podcasts that won’t go away, etc.
<Edited by Host>

Answer 1

From the top of the page where the scripts live...
The general method of use is to download the script to a folder of your choice, e.g. your Desktop, Downloads folder or create a folder at ...\iTunes\Scripts. Select a playlist or highlight some tracks in iTunes and then double-click on the script to execute it. If no specific tracks are selected the script will try to work with all tracks in the current playlist. Some scripts offer a choice of track by track confirmation of changes or fully automatic processing of the selection. Many of the scripts can optionally display a progress bar while running.
You are strongly advised to backup your entire library, or at the very least the iTunes Library.itl file, before use. Test the behaviour of your chosen script on a small group of files first to make sure it does what you want before applying it to large numbers of files.
Most builds of Windows will execute *.vbs scripts when you double-click them. If that doesn't happen then you might need to visit the Add/Remove Programs or Programs & Features control panel to enable the Windows Scripting Host. I can track down details if you have issues.
Backing up and restoring data is an area that is often glossed over. Most people don't try to learn much about it until they've lost something important. (Me too )
If your iTunes library was in the usual layout then normally copying the whole iTunes folder from the User's Music folder in the old computer to the User's Music folder in the new one will usually work fine. Ideally this is done before iTunes is installed so that there is no empty library to replace, and all settings are picked up from the old library. This post contains more details.
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