He's no Hugh Hefner, but Eric Weber is passionate about his work too. "I love it," says the 38-year-old writer and publisher. "I'm sexually obsessed." Fortunately, he channels his monomania onto paper. He didn't so much rise from obscurity as sneak out from under it with his 1970 sexy sleeper, How to Pick Up Girls! The book, which he produced himself, has since sold more than 650,000 copies and grossed $5 million. Realizing he had stumbled upon a seemingly insatiable market, he cranked out such sequels as How to Pick Up Women, Winning With Women and The Shy Person's Guide to Love and Loving. Weber has since turned his collected works into a cottage industry. In 1978 he wrote the treatment for an ABC-TV movie based on his first guide. He teaches courses on foraging for females at Network for Learning, an unaccredited but popular Manhattan education program.

And to think, only 15 years ago Eric Weber was just another shy and lonely guy looking for love in all the wrong places. He was making mostly money then, not love, as a junior copywriter at Benton & Bowles ad agency in New York. "I began noticing the women my mother always said I should marry," says Weber. "They were attractive, they were well dressed, they went to good colleges, they had good jobs. I said, 'Aha! I've got a good job. I should be dating some of them.' But they looked terrifying to me. I'd see them coming out of Bonwit's, and I would quake at the prospect of walking up to them and saying, 'Hi, I'd like to meet you.' "

How do you get to know such women? Eric, a New York University graduate in creative writing, decided to go to the filly's mouth. He interviewed single girls to find out what would work on them. He built up his confidence, learned the tricks of the trade—and met some nice women on the job. "I picked up my wife, Joanna, in a singles bar while I was doing research for the book in 1965," remembers Weber. "This pretty, very young-looking blonde tried to squeeze between me and a friend. I blocked her way and she said, 'Excuse me,' and I said, 'No.' She said, 'Why are you doing this?' and I said, 'Because you're much too pretty to let get away.' "

Corny? No more so than the 50 other "great" opening lines in Weber's first book, including: "You're Miss Ohio, aren't you?" "Are you French?" "Are you following me?" "Are you a model?" "Don't tell me a beautiful girl like you doesn't have a date tonight?" and "Please pass the ketchup." Other advice includes: "Talk dirty. Women love it," and "Museums are fantastic places to pick up women, especially if you are the serious, intellectual type." Some find Weber's words more sexist than sexy. But he has made at least a small bow to women's lib. In later editions of his books, he doesn't call them "chicks" or "broads."

Weber spent three fun-filled years doing research. By 1968 he was married to Joanna and decided it was time to stop looking and start writing his book. Many publishers rejected it. Recalls Weber: "One day I was sitting on my analyst's couch, complaining as people do. I said, 'I've worked thousands of hours on this book, and it's got to sell better than ones about house-plants in Hong Kong.' My analyst replied, 'You're in advertising. Promote your own book and sell it yourself by mail order.' I got so juiced up by the idea, I could hardly finish the hour." When the session was up, Weber, who has been in therapy for almost two decades, raced to a newsstand to buy a copy of Penthouse. He called the magazine to price a third-of-a-page ad, which was $725—three-quarters of his life savings.

The money he used publicizing the guide was well spent. With the orders that came in, he hired a printer. How to Pick Up Girls! continues to sell, at $4.95 for the paperback in stores or $11.95 for the hardback through the mail. The book boom—including four foreign editions—sprang Weber from another ad job, as associate creative director of the Young & Rubicam agency.

Although his father, Alex, who is president of a chain of bakery supply plants headquartered in New Jersey, liked Eric's book, his mother, Doris, a psychotherapist, "was stunned that I would put my name on it." Even Mom, though, approved of the financial rewards his words have brought him. With earnings of more than $1 million from the 16 books his small Symphony Press has published, as well as his other ventures, Eric lives comfortably with Joanna, 38, and their four kids, 3 to 10, in Tenafly, N.J.

He attributes his success as a mating guru to an innate ability to understand the problems and idiosyncrasies of both sexes. To quote from his chapter "How to Get Women to Pick You Up": "...hang around in places where there are scores of women and almost no men. For example, join a ballet class."