You can get FREE (after initial "build") high definition television in most areas. In fact, if you're within 120 miles of a tv station, chances are, you'll be able to get their channel.
The first thing you need to do, is consider your location:
What TV stations are around you, and broadcasting.
If you're in a semi-urban area, you're probably in an excellent area.
If you have very little around you, unfortunately, this will not work for you.
If you're in an area like Toronto or Buffalo, you can access two market's worth of channels, giving you 25 or more channels.
So, to begin our first step:
and put in your latitude and longitude to see what TV stations are around you, and their approximate distance away.
If you don't know your latitude and longitude, visit this site:http://www.gorissen.info/Pierre/maps/googleMapLocationv3.php
which will give the latitude and longitude of anywhere you click.
Just move around and zoom in to your location to get the most precise value.
Make a note of which stations are closest/you want to pick up, and what direction they are from your place. (Just general direction, for now.)