When Jason Matthews is in the Surf Shop, his father states that the especially sturdy surf board he is building is for "Laird". He is referring to Laird Hamilton, one of the premier big wave surfers in the world.
When Alexandra Hudson (played by Shannen Doherty) first arrives on the show, she is coming out of her limo and is greeted by a valet. He asks her how she likes Hawaii and she replies, "It beats the hell out of Beverly Hills." This is an obvious reference to her days as Brenda Walsh on the teen soap Beverly Hills, 90210 (1990).