Many people come to Hawaii expecting to see a traditional Hawaiian luau, and there are plenty of places that claim to offer this experience, such as Paradise Cove , and the Polynesian Cultural Center. I have not been to either, but I have heard from more than one person that these are both very expensive tourist traps, and really aren't very authentic (I just checked the price and they start at US$83 for tickets at the Polynesian Cultural Center. My suggestion: meet some local Hawaiians on your trip and head to their home for a true Hawaiian luau experience.
I plan to post some luau recipes this week so perhaps you can try having a luau at your home - you may not be able to feel the breeze of the ocean blowing through your hair but no-one said you can't pull out the brightest aloha shirt you have and party! Enjoy the week!