Can anyone point me to a good article that discusses the requirements of the Electronic Communications Privacy Act regarding monitoring unauthorized network use and notice that must be provided to unauthorized users?

The DOJ has some pretty specific guidance regarding banners, consent, monitoring and privacy related to the ECPA and the 4th Amendment.

Try this link:
http://www.cybercrime.gov/s&sappendix2002.htm

-g

Thank you, that's very helpful. I appreciate it!