Rob Mitchell (pictured) has been named executive editor of the Novato Advance by Publisher Paul Hutcheson. Mitchell, 29, has served as sports editor at the Advance for the past year. He takes over the position held for four years by Dan Stebbins, 64, who is moving to Tucson, Ariz. Mitchell, who comes from a family that owns two daily newspapers in Vermont, was honored last month by California Newspaper Publishers Association for the quality of his writing.