Zeus Bot warnings from Cox

I received the dreaded  "Compromised Computer Notification from Cox Communications" from Cox. I called cox and could not get any additional information. I have checked all my machines for malware and all come up clean.  I would like to find out what triggers the warning from cox (what external IP was it trying to hit, etc.) so that I could find out which machine internally was causing the issue.  Who should I contact to get this information so I can resolve the problem.  I have the tools to analyze my traffic thru my router but need to know what the needle in the haystack looks like.