No shortage of websites in the US. But tourist information tends to be organised at state rather than federal level, so while there's plenty out there, it can be hard to find. Towd.com, the Tourist Offices Worldwide Directory, is the best place to start looking.
Flying
All the usual suspects - OTC (otc-uk.com), expedia.co.uk, ebookers.com, flynow.com and travelocity.co.uk - are worth consulting for cheap fares. My own experience suggests that while the US-based airlines will accept UK bookings, they rarely extend their specials to British residents. An exception is American Airlines (aa.com), which has seats available from £184 until midnight on Monday. Cheaper transatlantic tickets and the DVT scare have led to a boom in premium economy on virginatlantic.com (or World Traveller Plus on britishairways.com): you can usually upgrade for £150 each way. For internal flights, try southwest.com.
By bus
How can you get from Boston to New Orleans for $69? By Greyhound, of course. This fare is only available 14 days in advance, and you can only book it with a US credit card - so it would help to have a friend over there. Alternatively, an Ameripass costs between $135 for four days and $495 (less for students) for two months, and it can be booked on-site.
By train
Amtrak (amtrak.com/international) isn't particularly expensive, either, although booking a cabin puts the price up substantially. A 15-day pass costs $295 off-peak and $440 during the summer. Timetables are, by British standards, remarkably simple: they come in PDF format for the longer routes, and can be printed out.
Driving
Rand McNally (randmcnally.com), the Michelin of America, has lots of tools for planning a road trip and can calculate the route. Anyone with the slightest interest in the kitscher elements of the wide open spaces should visit roadsideamerica.com and driveinmovie.com.
Staying
As one reader asked this week after finding hotel rooms at half the price quoted on UK websites: "We were sorely tempted to book, but you do hear awful things about people being ripped off. We just wondered whether you've heard anything about them so that we can minimise the risk of losing our cash." Well, I can't vouch for every hotel agent, but as long as you take the precautions of ensuring the site is technically secure, printing out the reservation details, finding a contact number and calling the hotel a few days before arriving to check on the booking, these bargain-basement sites should be fine. Many use the same reservation database and come up with similar offers. Try 4hotelrates.com, bedandbreakfast.com, motels.com and bestinns.net/usa.html. Alternatively, if you want to book with an agent with a UK base, visit placestostay.com, hotelnet.co.uk, expedia.co.uk or ase.net.
Visiting
Overwhelming. However, go-unitedstates.com makes a decent starting point, as do fodors.com and seeamerica.org/default.asp. Other notable sites include desertusa.com, a comprehensive guide to the drier parts of the US, and us-national-parks.net or nps.gov for advice on visiting national parks. Ghosttowns.com has its fans. Ski-guide.com is a portal with details of every ski resort in North America, while gorp.com will appeal to outdoor enthusiasts. Don't underestimate, however, how useful state and city websites (particularly bostonusa.com, nycvisit.com, sfvisitor.org and lacvb.com, for instance) can be.
Eating
Again, fodors.com has recommendations - or try zagat.com, or the formidable Diner Directory (astro.princeton.edu/%7Egoldberg/diner.html).