2 to trust: Spybot - Search & Destroy (FREE)
& AFAIK also this one:
Spy Sweeper http://www.webroot.com/wb/downloads/index.php

Other trusty tools to have around & are safe around LW are:
ad-ware (FREE) & also Peerguardian (FREE)

There is a spykiller forum which reviewed those on the market & Spybot got the thumbs up whereas a great many others didn't for one reason or another. And some others have spyware themselves lol. And of course some don't work well around p2p programs b/c they see magnet links as spyware.