Kaye Gibbons, popular author of seven bestselling novels that between them have sold more than four million copies, is moving to Harcourt in a seven-figure deal just signed with executive editor Ann Patty at the house. One of the two books covered in it will be a sequel to her first, and still most popular, novel, Ellen Foster, for publication next fall; the other is called The Lunatics' Ball. Patty signed with agent Joy Harris for North American rights. Gibbons was originally published by Algonquin, later by Putnam, and her books have been paperbacked at Vintage and HarperCollins.