You need more than one green bar in the connection bar to be able to search & download files. If only one green bar it means you have a connection problem.

Same issue here. I have 5 green connection bars, and no searches result in anything at all. I could not seem to find any "preferences folder" in Limewire...Please help

Check in the thread below (even though your LW is connected) for info about how to find the prefs folder(s). Remember that if you've used much older versions of LW in the past, you might have 2 folders... then you should delete them both
If LW Will Not Connect

Did you also try the other 2 fixes in post #3?