Which version of LW are you using? If using LW 4, then see the links within this thread:
How do I chat?.
Some people just open their mouths when others are around & suddenly chat happens. Amazing how humans developed that ability. lmao
Sorry about that silly joke.
Right-click the top of the heading bars of the search results window, download window & upload window. Choose to show Chat from the drop down menu. You will see a smiley for those who have chat enabled. You can only chat with those who have chat enabled.
LW 5 is a different kettle of fish. Off hand I cannot remember if chat is even an option. In LW 5 they took out most of the advanced features to make it a program for dumbies who just want to download with little fuss.