Here's a current map of HNL (although not to scale): http://terminalmaps.hawaii.gov:8080/hmaps/hnl

The Hertz location is in the Terminal 2 parking garage at the arrivals/baggage claim level. If your flight arrives into Terminal 2, then it's a quick walk across the roadway from baggage claim to the location, There's a separate line and rep for Gold members and that's where you obtain the keys to your assigned car and printed rental agreement. You'll be informed of the parking lot space (and floor of the garage) the car is in and you just drive off after that. As an aside, a Jeep is about the last thing I would want for a rental at HNL; I much prefer cars that blend in with the locals so when I go to the beach, there's less risk of being targeted for a break in / smash and grab.