Shocked, scared, in denial. Salt Lake County resident Roberta Woody remembers how she felt the moment she found out her identity was no longer her own. "It's been terrible, it really has," she said.

Woody, who shares her Social Security number with a man she has never met, is the perfect example of how a certain type of identity theft works.

Through federal investigators, Woody learned her number was probably stolen years ago out of her employee files. The thief then typed her nine-digit number onto a counterfeit card and sold it to an illegal immigrant. The immigrant bought the number so he could get a job in Utah.

This week, a KSL-TV investigation uncovered fake cards being sold on a street corner in Salt Lake City. Authorities told KSL that 900 South and State Street is known in other states, and in Mexico, as the place to go if you need to buy a fake card in Utah.

All it took was $50, and a salesman standing on the corner was ready to sell. A hidden microphone picked up the deal:

"My friend's sister is looking for a Social Security card," one man says, in Spanish, to another man.

"My friend, he can do it. How much?" the second man, "Juan," asks.

"I don't know. I need to ask him."

The man steps back. Others approach. He asks what name to put on the card.

"Rena Patel, Rena. It costs? The sure cost, 50? Is that OK? 50. Yeah, 50."

Juan randomly picks the number, one that could be anyone's Social Security number.

Three hours later — at the same corner — Juan hands off a fake card, then takes off with the money.

Fifty dollars bought something that might look real to some but not to Lt. Tony Garcia. "Looking at this card, holding this card in my hand, I can tell you I'm 100 percent sure it's fraudulent," he said.

To the trained eye, the card's texture is one clue that it's phony.

Garcia works for the Utah Department of Public Safety, which formed its own identity theft squad this year. So far his unit has made nearly 200 arrests in Utah and confiscated 150 fake Social Security cards.

Garcia explains how the crime works: "You make contact with an individual who asks you what you want. They leave for an extended period of time, four or five hours. They come back. They're very cautious. They have lookout people. They then make contact with you, you pay money for the card, they go their own way."

Garcia and other law enforcement officials confirm that sometimes the Social Security numbers that are sold are stolen out of neighborhood trash cans or lifted from employee files, like in Woody's case.

They add that a growing number are just made up and typed on a fake card.