Kevin, you'll need a visa if you want to stay more than 3 months or work. I'd go to London and visit the Embassy as a matter of priority.
Driving on the other side of the road isn't so hard especially if you've driven on the continent. You'll find cars and petrol incredibly cheap, housing depends where you look, food is generally cheap and servings enormous! Also, the US is wonderfully diverse. You'll find a wide range of communities most of whom will do their best to make you welcome.
Good luck,
j.R
"... They ne'er cared for us
yet: suffer us to famish, and their store-houses
crammed with grain; make edicts for usury, to
support usurers; repeal daily any wholesome act
established against the rich, and provide more
piercing statutes daily, to chain up and restrain
the poor. If the wars eat us not up, they will; and
there's all the love they bear us."
-- Shakespeare: Coriolanus, Act 1, scene 1