travelling from the UK

Hi all,

i'm thinking of doing the wild western perhaps sometime next year, I'm from the UK and i've done the usual pricing of the package, pricing the flights etc. however, what is actually required for british people to go into the usa as alot of websites seem to contradict each other.

Will Contiki advise me on what documentation I need when I receive paperwork etc from them? Or do they leave you to it? The FAQ mentions visas, but only advises to contact "your visa service or travel agent".

I'm in two minds of weather to book direct with Contiki, or book through an agent, can anybody share any opinions on which is better? I feel as though because its my first contiki trip on which I'm travelling solo, I might be better booking through an agent as it would be just me to mess this up!!! Can anybody shed any light on which is better? I'm totally clueless to these planned trips as whenever I go ski-ing etc (austria, which is why i am so naive with visas etc.) I have always booked the stuff my self independently, but which is better with this kind of thing?

I know thats quite alot of things to ask, but I'm totally clueless and hopefully somebody can point me in the right direction, or perhaps tell of a personal experience with some of the above.

Cheers,

Karl.