You’ve read all of your free items this month. To register, get added benefits and unlimited access to articles, Become a Member. Already a Member? Sign in. Advertising Age Article Abstract GM Moves Regional Dealer Media Biz Out of Starcom Unclear Which Car Brands Are Heading to Martin Retail, Velocity By Jean Halliday, Published on October 03, 2008 0 Want more Access, Content & Connections? Upgrade to Membership. We are glad you are enjoying Advertising Age. To get uninterrupted access and additional benefits, become a member today. Become a Member Already a member? Log in.