In reply to:
Unless you haven't synced yet. In that case, you can revert (or whatever it's called in emplode) to whatever's still on your empeg, losing any changes you made in emplode since you last synced.
And the easiest way to do that is to simply close emplode without doing the "sync" command.
Another way to find the songs (if there was only one copy of them in all of your playlists) is to do an "Advanced Search" for "refs=0". This will show all of the songs on your player that are not in any playlists. You may find a few things in here that you
thought you deleted but are still taking up space on your player.
Then, as Tony said, simply recreate that playlist.