One of them is a band from Nashville. Ben plays piano and performs the vocals, Matt whacks the drums and Will is on bass (and whistles).
There is also a Swedish powerpop band with the same name.
There is also a dutch melodic punkrock band with the same name. Who released five albums. Two of them produced by Bill Stevenson of the Descendents/ALL. Their most recent record is called 'Right Now!' and is released in September 2009 http://www.myspace.com/coopertheband
There is also a Spanish artist, Alejandro Diaz, who used to be in Los Flechazos...