How do I find what HD channels are available in my area over the air?

The Consumer Electronics Association has a great web site that assists the user in determining what channels (HD or otherwise) are available in your area and how far they are from your specific zip code. It also tells you what compass heading they are so you know how to point your antenna. The link is http://www.antennaweb.org/aw/welcome.aspx. Click on the "Choose an Antenna" button and type in your basic info (only where there is an asterisk) and follow the instructions.