Where is the OBD Connection on a 2001 Hyundai Elantra?

It should be on the driver's side inside the car. Look along the dash below the steering wheel. might be back a little bit, just look along the plastic down there. if you still can't find it, take the car to an autoparts place such as O'Reilly's, Autozone, Advance, etc. The employees there should be able to show you.