Just a warning to anyone travelling to USA you need to fill out a ESTA form which basically allows you to fly to the US. There are loads of sites through google offering this service and charging from £12 to £100! This service is completely free of charge and available here https://esta.cbp.dhs.gov/.
This isn't a visa it just allows you on the flight list and is compulsory.
Posting this as I read an article about it in Which magazine and thought I should share the info.