"You've gotta have art," according to an old advertising campaign by the Detroit Institute of Arts. Emily Zauzmer, 17, of Dresher, Penn., agrees, and has self-published and donated copies of a book designed to introduce art to young people to the DIA. Thomas Guastello, chair of the Oakland County Art Authority and a former Macomb County legislator, has contributed $1,000 so she can print and give away more.