In a trail blazed by such time-killing debates as Mary Ann or Ginger, the hot online either/or for ’99 looks to be…Cindy Margolis or Pamela Anderson Lee for Internet poster girl? The argument has been zinging since an April Wall Street Journal article touted Lee as the Web’s ruler, with a ”Gross Net Product” of about $77 million in Lee-related online sales a year — fueled in large part by a certain home video. That doesn’t make her Queen of the Internet, snipe fans of Margolis, who has won that Yahoo! title three years running. They have a case: Margolis’ 60 million photo downloads have earned the model-actress (Austin Powers 2) induction into 1999’s Guinness Book of Records. She’s also a big draw on talk shows. Her secret: She e-mails her database of 43 million ”cyberbuddies,” gleaned from her site (www.cindymargolis.com), and asks them to tune in. ”Some people do a movie and then go on the Net, but I’ve parlayed the Internet into a career,” she says. As for Ms. Lee, Margolis demurs: ”There’s no rivalry. I love Pam.” No word about where she stands on Mary Ann versus Ginger.