Oxygen Network has ordered up a second season of “The Janice Dickinson Modeling Agency,” which begins production this week.Reality show chronicling Dickinson’s attempt to establish her own business is Oxygen’s most successful original series. Second season will take on an expanded one-hour format. Women’s cable net also ordered a related holiday special, “Christmas With the Dickinsons,” for December, preceding the show’s second-season launch in January. Upcoming cycle will take a closer look at the lives of the models as well as Dickinson’s volatile relationship with her business partners. Stuart Krasnow exec produces with Kevin Williams and Dickinson.