How Do i research a hawaii license plate to find out the adress the car belongs to,for free?

Hey this guy parked in front of my mailbox and left a truck there,its irritating, and the lazy cops wont do anything because its 3 feet from my driveway? It is a danger for the people coming off the highway,the HPd(Honolulu Police Department) said that the guy lives in my neighborhood but that's all they can tell me. I want to find the house so i can tell them bout ther truck,?????