Paradise Cove is one of the better Luaus on Oahu. They do have buses that shuttle you from all the major hotels and you would need to make this arrangement when you book it.
You should be aware that the Paradise Cove location is located about 25 miles west of Honolulu in the Ko Olina area next door to the JW Marriott Resort and Spa. I mention this so you are not surprised by the length of the bus ride. The setting is quite private and beautiful. I also mention it because a cab from anywhere besides the JW Marriott would probably be prohibitively expensive.