Many cities believe targeting johns to cut demand is the best way, among them Chicago, Raleigh and Durham, N.C., and Arlington, Texas, where pictures of those arrested for soliciting prostitutes have been posted on police Web sites. Other cities that have tried the shame approach include St. Paul, Minn., Chattanooga, Tenn.; Cincinnati, Denver, Detroit, Los Angeles, Knoxville, Tenn., and Omaha, Neb.
Some cities have seized the cars of those who solicit sex. Some have sent "Dear john" letters to their homes so their families can learn what they've done.
Such crackdowns can backfire, though. In Kansas City, officials posted pictures of men arrested in prostitution cases on TV, but stopped the practice. Police Capt. Rich Lockhart said the program was a success at first, snaring some local lawyers and ministers.
"It actually was quite effective, especially initially," he said.
But as the affluent and educated learned of the dangers, police found they were arresting more street people as customers in the city's prostitution-infested areas.
"The problem's always there," he said. "We didn't arrest any fewer people. We just arrested different people. It's one of those problems that's not going to go away."
He said the effort to curb prostitution is "a little like being on the hamster wheel. It's very tiring at times."
Other cities have required men to stay out of areas where prostitution flourishes or to attend schools like the one Norma Hotaling formed in San Francisco.
A one-time prostitute, Hotaling started SAGE (Stand Against Global Exploitation) 13 years ago, and the organization runs a class aimed at preventing recidivism among the clients of prostitutes. The program educates first-time offenders about the dangers of prostitution and trains them to build real intimacy out of their fragile personal relationships.
Michael Shively recently presented preliminary results of research he did for the National Institute for Justice on the effectiveness of Hotaling's program. Shively, who works for a social science research company in Massachusetts, found the program reduced recidivism and was cost-effective since fees were paid by offenders.
He said his two-year study also had identified about 200 communities nationwide "that do some kind of a shaming effort."
"Most of it is posting in the newspaper or on a Web site the name and sometimes more information, sometimes pictures, of people who get arrested. Far more do it for the prostitutes," he said.
Hotaling said she prefers education of prostitution clients and opposes publicly shaming customers to combat prostitution because it shames their families too.
"Regular guys cross the line into prostitution without blinking an eye," said Hotaling.
Carol Leigh, a San Francisco sex worker rights activist, said Spitzer's fall - he resigned last week, days after being outed as a client of a high-dollar prostitution ring - was more proof that government should decriminalize prostitution to protect sex industry workers.
"These laws breed hypocrisy," she said, finding some sympathy for Spitzer even though he had worked to increase penalties against the customers of prostitutes.
David Bigeleisen, a San Francisco criminal defense lawyer, said he has been working to propose legislation to permit prostitution houses in California to be licensed or zoned like taverns.
"Sunlight is better than darkness on this. You wouldn't have to have a bordello in the same neighborhood as a school," he said. "Laws against prostitution don't have much effect stopping prostitution but they put it underground and it results in a lot of exploitation of women."
In New York, attorney Ron Kuby said the criminal justice system might not be ready for tougher laws, the kind Spitzer advocated.
"Most judges regard prostitution as a largely harmless vice, a commercial transaction for sex," he said. "What's the difference between that and a noncommercial transaction for sex? Kristen making $2,700 an hour with her clothes off, and the people who complain wouldn't mind if she was making minimum wage mucking out toilets with her clothes on."