ob1, the ball position varies a bit for all of us, including the pros.
Generally for a driver the ball is teed up just inside or inline with the LEFT heel. Shorter irons are generally about mid stance.
Some players will tee up a driver further back, some further forward. Some will move the ball progressively further back for each club, some will play all tee shots from the same position. It's largely what gives you the best results.