Audacious

Uninstalling/reinstalling won't help; the playlists (or lack thereof) are stored in your home directory (~/.config/audacious).

If you have the "Open files in a temporary playlist" option enabled (the default), you can just open any music file (Ctrl+O). Audacious will automatically create the "Now Playing" playlist for you and add the file you opened to it.

If you don't have that option enabled, you can run "audacious --enqueue-to-temp <some music file>" to accomplish the same thing.

And for anyone else who might wonder how to restore the "Library" playlist:

1. Enable the Search Tool pane by clicking on the "Search" (magnifying glass) icon in the toolbar.
2. Set the path to your music library at the bottom of the Search Tool pane, if you haven't already done so.
3. Click the "Refresh" icon at the lower right of the Search Tool pane.

Audacious will automatically create the "Library" playlist and add your entire music library to it.

Thanks. That worked.