I like to see the variety of leis and watch them being made. When we stopped in last week one of the lei sellers was making this beautiful haku lei (a lei worn around the head like a garland).
Do it yourself on Oahu:
Directions: The lei stands are well marked when you drive to the airport. Head towards arrivals until you see the sign for the lei stands on your left.
Hours: Each lei stand has its own hours, but from talking to one of the vendors it sounds like you should have no problem purchasing a lei as early as 6am and as late as 10pm.
Parking: Free parking directly in front of the lei sellers.
Prices: Better than your local drugstore or grocery store. Prices range from $5 to $20 or so. Some vendors will bargain with you, especially if you are buying multiple leis.
To see lots of great photos from around the world, check out Photo Friday at Delicious Baby.