Hi Joseph Rose,
With Time Machine, you don't need to find a specific file, you simply need to go back in time to the date you want to restore from, open the Music Folder and choose the iTunes Folder.
With Time Machine you can go "back in time" to restore files, versions of files, or your entire system. Make sure your backup drive is connected and mounted (if not, Time Machine will alert you that "Your Time Machine backup disk can't be found."
If prompted, enter an administrator name and password to proceed with the restore.
Restoring specific files or folders
Choose Enter Time Machine from the Time Machine menu and the restore interface appears. You can literally see your windows as they appeared "back in time."
You can use the timeline on the right side of the window to reach a certain point back in time (the timeline shows the times of all backups on your backup drive). If you don’t know exactly when you deleted or changed a file, you can use the back arrow to let Time Machine automatically travel through time to show you when that folder last changed.
Note: Dates in pink indicate the data resides on your Time Machine backup device. Dates in white indicate the data resides on your Mac. In OS X Mountain Lion and Lion, portable Macs have the feature of local snapshots. See thisarticle for details.
To restore, select the file/folder and click the "Restore" button. The file will automatically be copied to the desktop or appropriate folder. If the file you are restoring has another file in the same location with the same name, you will be prompted to choose which file to keep or keep both.
I hope this information helps ....
Have a great day!
so I wanted to try going back to a previous version of the iTunes Library.xml file.
I enter Time Machine, and as soon as I back up in time, there are no copies of those files whatsoever (iTunes Library.xml and iTunes Music Library.xml).
It looks like Time Machine does not backup the .xml files. Have a look at
About the iTunes Library.itl file
This file is a database of the songs in your library and the playlists you've created. Some song-specific data is saved in this file. If you delete the file, iTunes creates a new, empty copy when you open the application, but any playlists, song ratings, comments, or other information you created is lost. The iTunes Library file is only used by iTunes, and is the only one backed up by Time Machine on OS X.
The .xml file contains similar data to the .itl file and is not included in the backup.