The Knot is an award winning wedding guide website. It provides checklists for brides, grooms, and the rest of the wedding party. It helps you plan the ceremony and the honeymoon. Couples can register for gifts online. There's also help with organizing the budget and the guest list.
With sections of advice for the Bride and the Groom, Newlyweds, and Wedding Guests, this site is truly useful. Wedding Guests can search Gift Registries. Brides and Grooms can create personalized wedding planners. On the Internet since 1997, this is a wonderful resource.