Hi - klez has been rampant since April of 2002. Google, you will get bunches of hits.
Any well known and regularly updated AV software will not let the payload in to your mail (payloads are variously named .exe, .bat, ... attachments).
The subject lines are varied. Your AV provider can give you a list of them.
The particular recipient (Dan Chisolm) and (bogus) sender Bill Brogden do not (necessarily) have klez. (It would be highly amusing if Bill did!)
But someone who has both your e-mail addresses does!
With Outlook you can perhaps narrow this down - select the email, right click, selct options.
You should be able to tell the originating mail server name (but not the real sender).
In my particular environment, all of my 'firends' who have it are sitting behind gtcom servers.
The real, total, and final solution: install Linux.
Regards and HTH, Guy