Putting book publicity ahead of personal safety, or perhaps personal sanity ahead of prudence, author-in-hiding Salman Rushdie waded into three London bookstores yesterday to sign copies of "Haroun and the Sea of Stories," his new book. Customers were agog.

Rushdie's first stop was his former neighborhood book shop, the Angel, in Islington, where he sat down to sign copies of "Haroun." The handful of customers who happened to be browsing at 11 in the morning were overwhelmed by "many many men in raincoats who seemed to have a stomach itch," according to Bill Buford, Rushdie's editor and publisher at Granta Books, who accompanied him.

Buford was referring to members of Britain's Special Branch, the security force assigned to protect Rushdie from would-be assassins and other ill-wishers heeding the call of the late Ayatollah Ruhollah Khomeini, who ordered Rushdie put to death nearly two years ago for alleged blasphemies against Islam in his novel "The Satanic Verses." Threats of bookstore bombings and a couple of actual bombings have made bookstores especially jittery outposts of this controversy.

The three-store whirl apparently was Rushdie's first real venture into the open from his involuntary imprisonment of the last 22 months. "Slowly," Buford said, "Salman is trying to reenter the world, doing the things a writer would normally do." Buford said he and Rushdie had made the decision in consultation with Viking Penguin, the parent publishing company.

The surprise visits were anything but normal, apparently. At another stop, the Owl Bookshop, Buford said customers "stood around gaping," as much at his mackintoshed entourage as at the phantom author.

At the third stop, Waterstone's in Hampstead, Buford said, after signing books Rushdie was determined to buy some books for himself -- this being his first trip (at least cognito) to any bookstore since early 1989. But the proprietors "insisted on giving him the books he wanted," Buford said.

Rushdie may have been invisible to the public until now, but he has not been silent. He has reviewed books for publications, including The Washington Post. Granta Books, the new publishing arm of Granta magazine, has published two pamphlets by Rushdie, and last winter he gave an interview to Newsweek and the Independent of London. Publication of "Haroun and the Sea of Stories," however, has found him even more accessible. He has granted recent interviews to CBS News, to the New York Times Magazine and Vanity Fair.

Buford said he had suggested that Rushdie tour the United States in conjunction with "Haroun," but that that idea had been nixed.