On the form given to you by the airline on the flight down you just write in where you are staying. Guess they don't want anybody just pitching a tent.
Doesn't take but a few minutes as they look over your paperwork.
After that get your checked luggage and pass through Aruba Customs. In over 20 trips there is usually 2 uniform Aruban Custom Agents standing by the exit door. They just look you over. Never been stopped.