They are pretty hard due to find due to the reason you stated. That said, there are a couple.
BitDefender has an anti-spyware component. It's not in any repositories, but it can be downloaded free for personal use.
PacketFence is another option. It does a lot more than spyware so it may be more complicated, but it you don't have to fill out a form to download the RPM file from their website.
I've never actually used either of these myself though.