Tough loss.

Any way you could go back to the area with a large retrieving magnet or metal detector? Harbor Freight typically has some pretty strong magnets available for cheap. My grandfather drove tow trucks and had a pretty strong magnet on a rope that he used for finding lost tools (or misc. car parts) in the snow.

Of course if it was in the plowed area of a road you probably won't find it, but otherwise it will probably be sitting out there until the next good thaw or even spring.

-Eric