Still looking for a solution? I can see a few different possiblities:
1. Turning up logging on the print server. I'm not sure if the number of pages would get written to events.
2. Have something watch the print queue and report back if the number exceeds X.
#1 would likely be easiest because reading from the Event Viewer is relatively easy. #2 seems to require some complicated Win32 API calls.
Marco