I am actually writing a fanfic based on this, as I have said on other threads. Anyway, I've written about the first responses, including a massive, global news broadcast of the dangers of Sword Art Online, and the confiscation of any unsold Sword Art Online copies and Nerve Gear consoles by authorities.
As for Akihiko, I have included a news report in the first chapter that mentions the Japanese National Police Agency and Interpol setting up task forces dedicated to locating and capturing Akihiko, as well as a phone and e-mail tipline.
As for figuring out how to disarm a Nerve Gear, in my fic, the task force working on confiscated, disconnected Nerve Gears. The task force includes both computer expert, and perhaps a person serving a prison sentence for hacking who has been offered parole in exchange for their help, in order to find a software-based method of disarming, and explosive ordnance disposal experts attempting to safely physically disable the device.