Norwegian actress Liv Ullmann and American real estate executive Donald Sanders were married yesterday in Rome at the American Episcopal Church of St. Paul's Within-the-Walls . . .

AIDS-stricken actor Rock Hudson is resting at home since his release from a hospital two weeks ago, but cannot go out, and his spokesman said he will not be attending the Sept. 19 Hollywood benefit to raise money to fight the disease. The benefit is to feature appearances by actresses Elizabeth Taylor and Shirley MacLaine, among others . . . New York Daily News columnist Liz Smith reports today that Hudson is working on a book with a collaborator to tell the story of his double life in Hollywood. It will be published jointly by William Morrow and Avon . . .

One of Italy's most popular writers, Italo Calvino, was listed as improved yesterday after six hours of brain surgery; he suffered a stroke Friday at his villa in Tuscany . . .

Gossip columnist Suzy has left the New York Daily News after 18 years to work for Rupert Murdoch's rival New York Post. In a statement released yesterday, Suzy said the Post "is so high spirited that nothing can hold it back -- just like me."