you can set up the leads in google analytics, under goals and with google voice, simple put the google voice # on there website, put a conversion tracker on the click OR just look in the google voice settings every week or month and say, $20 per call, AND a form inquiry put a tracker on that and set it at i dont now $10 and wala! and then put the price in google analytics and you GOT YOURSELF A CONVERSION TRACKING SYSTEM