General Motors Corporation (GM) and eBay Incorporated announced Monday they have launched a test program in California that will allow consumers to negotiate with dealers and purchase vehicles online. The car-shopping website (gm.ebay.com) marks a departure from the way new vehicles have been traditionally sold in the United States and is aimed at enabling GM to improve sales one month after it emerged from bankruptcy protection. More than 225 GM dealers in California are participating in the program, which runs for nearly a month. The website allows consumers to compare pricing across models and participating dealerships, negotiate prices, and arrange financing and payment.