Mountain View, CA-based TrialPay, an online payment provider, has raised a $12.7 million second round from Index Ventures, Atomico Ventures and ex-PayPal executives. The round brings the company’s total raise to $15.8 million, having previously taken investments from Battery Ventures, Ron Conway and Bob Pittman in 2006. The company’s strategy is to meld online payments with online marketing, so that a customer can get a rebate or discount on an item by doing business with a participating advertiser. This is supposed to a way of hooking online shoppers that may otherwise be wavering on a purchase. The company is in particular targeting software vendors. Advertisers that have signed up include Blockbuster (NYSE: BBI) and FTD.com. Release.