WASHINGTON - Joanne Kathleen Rowling, creator of the Harry Potter publishing phenomenon, gets a world-weary look when she hears the same questions: What's your secret? Where do you get your inspiration?

"If I knew where it came from, I'd go live there," she quipped during a recent appearance at the National Press Club. "Most of the ideas just come, though some I have to really work at."

And what about her amazing following? Her first three books about young Harry and his phantasmagorical adventures at the Hogwarts School of Wizardry top the best-seller charts, with U.S. sales exceeding 7 million books. But unlike "Star Wars," "Tarzan" or "Pokemon," this is not the result of a global marketing machine.

This is the work of a diminutive English writer, 34, who was unemployed a few years ago and sat hunched over a table in an Edinburgh coffee shop inventing Harry and his friends. She confided only in her sister. She was turned down by several publishers.

Bloomsbury took a chance, but made the author's name J.K. Rowling because of concerns that boys wouldn't read the book if they knew it was written by a woman.

"Why so popular? I've been asked that times without number," she said with a laugh. "I don't want to analyze it. I don't have a magic insight. And I don't write with an imaginary focus group in mind."

In a scene befitting a rock star or sports hero, Rowling was besieged by young fans at the Press Club, part of a two-week U.S. tour. She signed more than 400 books, and displayed an impish humor and no-nonsense style in answering questions from children and their parents:

- Advising would-be writers: "Read as much as you can. Realize that a lot of what you will write is rubbish. Persevere."

- Advising parents of young writers: "Don't tell them what they write is not realistic."

- On the Harry Potter series: "I will write seven books. When I'm done I expect a real sense of bereavement. That will be 13 years of work."

- On Harry's fate: "I know what will happen to Harry in book seven, but I'm not going to tell you - he's got quite a full agenda coming up, poor boy."

- How she came up with the idea for "quidditch," the airborne sport played on broomsticks that has a central role in the series: "Every secret society needs a sport, so I came up with this dangerous game. Like cricket, quidditch could go on for years and years, until the golden snitch is caught."

- On whether Harry and his friend Hermione will have a date when they get older: "No, but I won't answer for anyone else - nudge, nudge, wink, wink."

Harry Potter fever may continue to grow. The fourth book will be out next year. The movie version of the first, "The Sorcerer's Stone," is due out from Warner Bros. in 2001.

A few critics have complained of sorcery and violence, but Rowling says she writes "moral books" with Harry, Ron and Hermione as "innately good people."

Besides, she noted, "If you were to ban all books with witchcraft and the supernatural, you would throw out three-quarters of children's literature."