Is there a way or a program that can possbly tell you IF there is some type of keylogger program installed on your PC?

Long story short, I work in a small office and I suspect our tech guy of using such a program. (without the owners consent). Our owner could really care less about the whole thing but I hear things that the tech guy says that makes me suspicious. I really don't have anything to hide, but the whole thing pisses me off (besides being illegal more than likely). Our office consists of approximately 12 onsight pc's tied into a server of some sort (another pc that sits in a corner). This tech guy has already admitted that he goes into the server and reads people's emails. I think the keylogging came about because several of us in the office got wise to him and took our conversations off of email and now use msn/yahoo messenger (we had it installed already because most of us use it to communicate with customers) to chat back and forth. This "tech" guy is basically a office manager type and really doesnt know much about pc's in general (I am the resident expert and believe me that's a scary thought!) We have an outside company that comes in and takes care of most of the pc work that needs to be done, basically our "tech" guy doesn't have a clue, he's just a nosey bastard with too much time on his hands!

Any info you can give me would be greatly appreaciated.

You can use these programs to check for keyloggers:
a² free
ewido security suite
Ad-Aware
Spybot S&D

When installing ewido security suite, under Additional Options uncheck:
Install background guard
Install scan via context menu

Important:
Please read this tutorial on Spybot S&D before using it. Spybot can do SERIOUS damage, if not used properly.

Helpful Tutorials:
Using Ad-Aware SE
Using Ewido

Great, thanks I'll do that and report back. I was wondering, do keyloggers have to be installed on the individual machines? Or is there a way to put it on our server and get all the pc's with one fell swoop?