Why is my 2008 Chevy Cobalt leaking water in the front floorboards?

Check around the door seals and check the drains in the bottom of the doors. Check to see if the heater/AC housing drain to the engine compartment is clear. You may have water pooling in the heater housing due to debris fallen into the cowl vent plugging the drain. You could get under the dash with a flashlight to see where water is coming in. Sorry I can't help you better but it's hard to diagnose a rainwater leak without seeing the car. If you want to find a specialist, here's a directory link for you: