In Concepcion, they arranged a tour bus at the local tourist office to Temuco.  There, they rented a car and felt very comfortable driving the rest of the trip.  They visited places such as Valdivia and Pucon.  Their favorite was Valdivia, which was very unspoiled.  Pucon is supposed to be a world-class tourist destination, one of those places where you can enjoy both skiing and hot springs.  My friend does not recommend it -- too American, too trendy.