Synopsis

Import module,
ipmo AudioBackup

List available commands,
Get-Module AudioBackup

Create new library, default location,
New-AudioLibrary

Populate library,
Get-ChildItem C:\Music -Rec -Inc *.mp3,*.aac,*.aa3,*.m4a,*.wma | Add-AudioFile

Read contents of library,
Get-AudioFile | Format-Table -GroupBy Artist

Output list of files needing to be backed up,
Backup-AudioFile | %{ $_.FullName } | Out-File C:\files-to-backup.txt

Read contents of backup media into library,
Get-ChildItem D:\ -Rec -Inc *.mp3,*.aac,*.aa3,*.m4a,*.wma | Add-AudioFile

Update existing library file with changes on your harddrive (after removal/edit of an mp3),
Update-AudioFile