Where is oil drain plug on a 2001 mustang with 3.8l?

The oil drain plug on a 2001 Mustang with a 3.8L engine is located on the bottom of the oil pan. To be more precise, it's on the lower front of the oil pan, generally towards the driver's side (but slightly off-center).

You'll need to get under the car to see it. It's a relatively easily accessible bolt, but be sure to have a drain pan ready to catch the oil.