Pop Singer for Outdoor Evening Reception

I'm in need of a professional singer for an outdoor evening reception at St Catherine's College where families will be mingling and meeting for the first time. The singer will be performing continuously, so a great vocal range and stage presence are a plus, but the most important quality to me is experience with similar events. Ideally, the singer's repertoire should include well-known songs, suitable for background music that will appeal to a wide audience.