Check out the worksheets on CarBuyingTips.com. They have an offer worksheet the lets you factor in the incentives (currently $750 on sedans, maybe $1,000 on coupes still), the dealer holdback, and allows a "fair" profit percentage for the dealer. You can control the varibles and see how the offers from different dealers compare to this worksheet.
BTW, I don't have a V6, but like many of here at DA, I worked my deal over the internet using the available tools like the site above and Edmunds and KBB for price and incentive research.
