Hi Taa,

Check out this thread (click on link) for more info: DELETING FILES FROM LIMEWIRE LIBRARY-DON"T! - File recovery advice!
Maybe try the Recuva program in post #2.

But as Blackhorse said, first of all do a search for some of the missing file names/extensions. Sometimes files stop showing in LW's library if the version of LW has been updated, but they may still be on your HDD