Coolent leak

i have a 2002 pontiac grand am v6. i have a coolent leak in the thermostat area thermostat and sensor been replaced but still leaking.any idea what could be leaking?

Somebody did not do a good job either installing these items, or missed a leak somwhere else that looked like it was coming from the thermostat. Take the car back to the shop and get it fixed properly. There should be no charge, except if there was another leak somwhere else.