Here is a list in order (with the most common first) of what laser guns are used in what state. Hope this helps, feel free to contribute

USA:
Arizona - Pro Laser III
California - Pro Laser III, LTI Ultralyte
Colorado - LTI
Connecticut - LTI Ultralyte, Stalker LZ1
Deleware - Pro Laser III, Stalker LZ1
Florida - Laser Atlanta, Pro Laser III, LTI Ultralyte, Pro-Lite, Stalker LZ1
Georgia - LTI Ultralyte, Laser Atlanta, Pro Laser III, Kustom Prolite
Hawaii - LTI Ultralyte, LTI 20/20
Idaho - LTI Ultralyte, LTI Marksman
Indiana - Pro Laser III
Illinios - Pro Laser III
Iowa - LTI Ultralyte, LTI Marksman
Kansas - Pro Laser III
Kentucky - LTI Ultralyte
Louisiana - LTI
Maryland - LTI Ultralyte, Pro Laser III
Massachusetts - LTI Ultralyte, LTI Marksman, Laser Atlanta
Michigan - Prolaser III, LTI 20/20, LTI Ultralyte, Stalker Lz1, Laser Atlanta
Minnesota - LTI Ultralyte, Pro Laser III
Mississippi - Laser Atlanta
Missouri - Stalker, Pro Laser III, LTI Ultralyte
New Hampshire - Pro Laser III, LTI Ultralyte,
New Jersey - LTI Ultralye, LTI Marksman
New York - LTI Ultralyte, Pro Laser III, Stalker, LTI Marksman
North Carolina - ProLaser III, Stalker
Ohio - LTI Ultralyte, LTI Marksman, Pro Laser III, Stalker, LTI 20/20
Oregon - Stalker, LTI Marksman 20/20, LTI Ultralyte, Pro Laser II, Pro Laser III
South Carolina - Pro-Lite, LTI Ultralyte
Tennessee - Pro Laser III
Texas - LTI Ultralyte, Stalker, LTI Marksman, Pro Laser III
Utah - Laser Atlanta, Pro laser II & III, Stalker LZ1, LTI Marksman, LTI Ultralyte, Prolite
Vermont - LTI Ultralyte
Virginia - Pro Laser III, Stalker
Washington - Pro Laser III, LTI Marksman, Pro-lite
West Virginia - Laser (unkown type)
Wisconson - LTI Ultralyte, Pro Laser III, Stalker, Pro Laser II, LTI Marksman