Hertz is in the parking structures directly across from Terminals (sides) A and B. It is no longer necessary to ride a bus to Hertz's main facility north of Orlando International Airport.
As at other airports with Gold service, you find your name and the parking stall number for your pre-assigned car on the large Hertz Gold board.
In addition, Hertz Gold members can now use Hertz Gold Choice to pick a different car. Orlando is one of airports that offers Hertz Gold Choice. (It's something I haven't tried yet myself because I've used National for my last few Orlando car rentals.)