The Cat Lady (Eileen Brennan) retrieves a double barreled shotgun from her house when she notices The Creeper posing in front of her scarecrow in the garden. She fires a shot at it but misses and it flees into her house, she then goes after it, fires two more shots from within before being killed by the Creeper. Apparently the shotgun was loaded with high explosive rounds judging by its effect on the scarecrow post.
Colt M16A2
M16A2 rifles (more likely are AR15 HBARs being that they are State Troopers) are used when the Troopers don Riot gear and confront the Creeper at the films' conclusion.
Winchester Model 1200 Shotgun
Used by local police officers who are killed by The Creeper in their patrol car. The Model 1200 is also used later (with rifled sights) by the State Troopers at their police station.
Beretta 92FS
Carried by various State Troopers as their sidearms.
Colt Trooper
A .357 Magnum Colt Trooper appears to appear several times, the first time in the holster of Officer Gideon (Jon Beshara) and later at the State Trooper Station. (These are educated guesses, gleaned from multiple viewings of the clips, however all the scenes with the revolvers are dark and hard to make out).
Glock 17
At least one Glock 17 is seen in the hands of a female State Trooper.
Unknown Revolvers
Several unknown revolvers are seen in the Police massing scenes, however, they appear to Smith & Wesson types, judging by frames and ejector shrouds.