Armed with a new study showing Florida's revenue-challenged state government will miss out on $450 million to $455 million in sales tax collections due in 2012, some big trade groups will step up their campaign today to prod the Legislature to go after taxes not collected by out-of-state online retailers. Online retailers that operate any stores or warehouses in Florida already collect the tax. But out-of-state retailers such as amazon.com and overstock.com have avoided collecting because they claim no physical presence here. Amazon collects the tax for its Florida affiliate vendors if they ask. The study was bankrolled by the Alliance for Main Street Fairness, which is backed by the Florida Retail Federation, Associated Industries of Florida and the Florida Chamber of Commerce. The groups expect to have bills considered in the January legislative session.