An interesting website that is, in part, pertinent to original props and wardrobe: www.lapdonline.org/art_theft_detail
Per the website:
The Art Theft Detail is responsible for the investigation of all thefts and burglaries when fine art is the primary object of attack. The detail also investigates fakes, frauds, and forgeries involving art. This unit has citywide jurisdiction and assists in protecting the artistic, cultural and historical heritage of a city of 3.8 million people covering more than 450 square miles. It is the only full-time law enforcement unit in the United States devoted to the investigation of art crimes.
The two detectives assigned to the Art Theft Detail target suspects who prey upon artists, art dealers, and collectors. The unit maintains close contact with the art community and provides stolen art information to galleries, art dealers, auction houses, museums, art associations, publications and other law enforcement agencies – both nationally and internationally.
There is some information, even though geared toward “art”, some is still applicable to original props employed in film and television.
There is also a list of “Collectibles” reported stolen, including props from the movie Predator 2:
movie prop from Predator II
alien skeleton
10″ high x 42″ long x 6″ wide
bone white color
LAPD DR# 96-0920354 (Case 5-2/96)
movie prop from Predator II
alien spear
7′ long, possibly retractable
made of copper and plastic
gold and bronze tint
LAPD DR# 96-0920354 (Case 5-2/96)
movie prop from Predator II
Predator mask
18″ high x 12″ wide
made of urethane and fiberglass
LAPD DR# 96-0920354 (Case 5-2/96)
movie prop from Predator II
throwing disc
10″ in diameter
made of urethane with LED lights powered by a 9-volt battery
LAPD DR# 96-0920354 (Case 5-2/96)
Jason De Bord