New visa rules came into force yesterday for those wishing to enter the United States. UK visitors will no longer be able to fill in the Visa Waiver form on the aircraft and must instead be pre-cleared with ESTA (Electronic System for Travel Authorisation) at least three days before departure. Already there are unscrupulous operators trying to charge money for this free service, so in order to save you from wasting money, here is the correct link from the website of the US embassy in London:
From the embassy's site:
Travelers don't need to have specific travel plans in order to register. Registration is valid for two years or the life of the traveler's passport, whichever is shorter. So far, 99.6% of those registering have been approved - most within four seconds.