I believe the Pentagon email addresses are first.last @ dod.mil "The Pentagon" is the common name for the building that houses the Department of Defense (DoD).

Since the SGC is classified, everything is routed through Peterson AFB. Carter's would be samantha.carter@peterson.af.mil You can follow that convention for everyone at Cheyenne since they've been there well over a decade or you could go with @norad.af.mil as Cheyenne is the name of the whole complex not the name of the base.