Had you changed the location of your saved folder from the default (for Windows - C:\Documents and Settings\your name\Shared)?
Normally, files have to be deleted from LW's library to disappear. People have done this by accident, not realising that their files will be lost. Sometimes, people may add their library to a media player (as a playlist) & they assume they can delete everything from LW's library afterwards & still have files saved...not saying you've done this, just giving an example.

Perth is on the west coast of Oz...the capital of Western Australia.