Beach Wedding Attire

I`m taking a cruise and getting married on a beach in St. Thomas. I have found a few possibilities for the dress I am going to wear, but does anyone have any suggestions for attire for the groom and his groomsmen? I don`t want them to wear tuxes, but I don`t want them to be too casual looking either. Any help would be greatly appreciated. Also if anyone has done this before any other suggestions would be great too. THANKS!!!