If Steve Martin, Robert De Niro, and Steven Spielberg can be had, so can you.

The Hollywood legends have each been a victim of art scams - Martin, most recently, as part of a giant art scandal unfolding in Germany.

The Dirty Rotten Scoundrels star paid $850,000 for what he believed was a 1915 painting by German expressionist Heinrich Campendonk. The actor-comedian told the New York Times that even experts were fooled - "the fakers were quite clever."

"With art, it's like the Wild West out there, totally unregulated, buyer beware," said the founder of the FBI Art Crime Team, Robert K. Wittman, now a Philadelphia art-security consultant. "You've got to protect yourself."

During his 20-year FBI career, Wittman was best known for rescuing stolen Rembrandts, Rodins, and Rockwells, but he also investigated several major scams - most notable, the Antiques Roadshow television scandal hatched by Main Line con artist Russell Pritchard III.

"Here was a guy who did appraisals on PBS - what could be more authentic than that?" says Wittman, who recounts the full Antiques Roadshow case in a chapter of his New York Times best-selling memoir Priceless, which is out in paperback Tuesday.

Wittman reserves particular contempt for dealers who peddle bogus antiques: When the author was growing up, his father was one of a cadre of Baltimore antiques merchants "working to make a living on small margins."

When buying art, antiques, or jewelry, Wittman says, it's often more important to scrutinize the dealer than the piece you are considering. Does he or she have a proven track record? "It's a lot like buying a car from a dealer," Wittman says.

Some companies also offer art title insurance, similar to property title insurance. "Some art costs as much as a house, so it's ridiculous not to consider this," he says.

Other considerations: Can the dealer produce a provenance that can be independently verified? Is the dealer willing to offer a written lifetime guarantee that the work is authentic?

Wittman concedes anyone can be scammed. Years ago, he bought a handful of purported Civil War belt buckles at a market.

"Deep down, I knew they were way too cheap, but I took a flier, thinking, 'Who knows?' " Wittman says. "To this day, I keep them in my drawer to remind me that if a deal sounds too good to be true, it probably is."

At noon Wednesday, FBI Art Crime Team founder Robert K. Wittman will appear on a philly.com video chat with Inquirer reporter John Shiffman, with whom he wrote his memoir, "Priceless: How I Went Undercover to Rescue the World's Stolen Treasures."