Longtime Nevadan and Republican Party leader Frank Fahrenkopf says he will step down as president and CEO of the American Gaming Association June 30.Fahrenkopf, 73, had been head of the AGA, the country's main casino lobbying organization, since its creation 17 years ago. Gambling industry leaders praised his efforts to build the respect for the industry."He has been a steady, thoughtful leader through a period of great change for our industry and has steered us through some of its most difficult challenges," said Richard Haddrill, chairman of Bally Technologies.When the AGA was formed, Fahrenkopf said the perception of the gaming …