You must be connected to the nutella network to be able to do a search (connection quality must be at least green (bottom left corner). If it's always red then Do this check (click this link.)
Else if you can't see the button, see this thread: http://www.gnutellaforums.com/showth...threadid=29533 It might also be related to the skin you have chosen for LW (View Change Skins.)