Concerned about the booming trade in online cigarette sales, New York state officials have begun using a variety of techniques to clamp down on the trade, saying New York City alone is losing more than $75 million a year in uncollected tax revenues because of the sales.In recent weeks, Attorney General Eliot Spitzer has been pushing local postal officials and private carriers to stop delivering cigarettes bought online. His office has also recently begun negotiations with credit card companies to block transactions of online cigarettes.These efforts were given added push recently as local officials from the federal Bureau of Alcohol,...