I have a car reservation. Is there a shuttle or other ground transportation from the terminal to Hertzto pick up the car when I get off the plane?

There is a monorail which takes you from the terminal to the baggage / transportation area. Go to the hertz counter and they will direct you to accordingly to pickup the car from parking lot just outside the baggage area.

Hertz is inside the airport. Just follow the signs. It's on the ground level I believe.

There is a train its go from the terminal to the garage where are all the rental companys