The journalists at RadarOnline.com have a tricky way of preventing other Web sites from lifting the documents they post. On Wednesday, an hour after Radar posted the court documents Jon Gosselin filed against TLC, which produces “Jon & Kate Plus 8,” TMZ posted the same papers. “We had stamped the documents with our logo, but an expert in photo shop can remove those, so we put other markings on the documents. Lawyers for RadarOnline, armed with the irrefutable evidence, contacted TMZ, which quickly removed the purloined court papers from its Web site. RadarOnline creator and Executive Vice President David Perel told us, “Theft is the sincerest form of flattery.”