Your LimeWire library displays the files in folders that you are sharing. To view the contents of a directory not currently displayed, simply add that directory to the list of shared directories.

You can do this by going to the Tools>>Options window and then going to the "Sharing" tab. You should see a field for shared directories where you can add whichever directories you like. Once you add the directory with the files you want, that directory will appear in your library.

Good luck!