Just to add to what Remoc said... once you find the folder where your files are saved, make a note of the location of that folder.

Now open LW > click on the 'My Files' icon > highlight Library > click on the 'Add Files' button.

Browse for the folder containing your songs > highlight the folder & click 'Add File(s)' if you want to add the whole folder. Otherwise double click to open the folder & then select files that you want to add from there.

If you can't find the files on your HDD, plug in your flash drive & browse for that drive instead when adding files.

If you want to change saved folder location in LW 5, go tools > options > transfers. Click on the Browse button in the Downloads section - there you can change location. Just remember to click 'ok' in that box & also on the main options page to save any changes.

And if you want to share files that are in your library... click on Library > right click on a file > add to list > Public shared.