Hi Capin,
The US TV market is very different from the UK and rest of Europe. There isn't a strong public broadcaster here and over-the-air TV is centered around a model with local affiliates taking a few hours a day from a network and programming the rest themselves, so there aren't any real national TV channels like exist in Europe.
Cable also started a long time before it ever got big in Europe, so the audience is used to paying for TV and doesn't find it strange. Many of my friends even pay cable companies to get free over the air channels because it's easier than putting up an antenna. As a result, the cable and satellite companies have a pretty decent lock on the market. A standard clause in any contract to get a channel on cable is that you can't broadcast it free to air, so what is up there is often encrypted.
The closest thing to what you are used to is Galaxy 19 at 97W, which carries about 200 channels FTA. Almost all are from overseas or are Christian TV stations.
There are a few other channels on other KU band satellite and you'll find PBS and NBC network feeds. KU is used by all the US networks for satellite news feeds too, if you're a news junkie. Otherwise, you'll have a lot more fun with a C-band dish, which brings in a bunch of US OTA channels, TV network feeds and stations from Canada and Latin America (for the latter, check you're in the footprint for Eutelsat 113 and 117). In North Carolina, you can also access a lot of the satellites over the Atlantic.
Martyn