10:30 (Dow Jones) The key to analyzing media stocks is....automobiles? Yes, it's true, suggest SG Cowen media analysts Ed Hatch, Peter Mirsky and Eric Handler, in this week's Media Money Manager. Automobile advertising is the largest category in domestic consumer media spending and accounts for about 17%, or $15 billion, the stock studiers say, using data from Competitive Media Reporting. By early fall, the analysts expect the car companies "to ramp spending back up to support new model introductions and to regain market share from the imports." Such an event, says the SG Cowen crew, could mark a significant catalyst for companies that depend heavily on TV advertising, like AOL Time Warner (AOL), Viacom (VIA, VIAB), News Corp. (NWS), and Disney (DIS). ( BS)