Singer and guitarist John Rzeznik, after fronting the Goo Goo Dolls for 25 years, has a simple formula for staying relevant. "We tour as much as possible," says Rzeznik, who appears with the band Saturday, July 23, at Tropicana Casino and Resort in Atlantic City. "No matter what happens with the record industry, that's where we do really well. And that's still the best way to connect with the people that like your band." Unlike most bands who hit their commercial stride early in their careers, these alternative rockers from Buffalo, N.Y., didn