As Apple rolled out its newest iPhone on Friday, dealers and buyers were anticipating the popular device in Asia’s thriving underground marketplace in as little as a few days. The iPhones are nothing new to Asia, where enthusiasts from Bangkok to Shanghai already sport fake and unlocked versions of last year’s models — unlocked so they can work with any carrier, not just the Apple-authorized ones. Now, electronics markets are preparing for an influx of iPhones capable of 3G, or third-generation, cell phone technology.