To help get local OTA channels in your area. Try this site.
http://www.fcc.gov/mb/engineering/maps/ Enter zip code:
Select satellite view on map:
Zoom in to house level:
Move location mark to desired spot.
Green channels= strong signal
Yellow channels = Moderate channels
From channel list select channel call letters. This will give additional info.
Including compass direction to tower. Also will denote HD channels.
Also link on Antenna Guide has some good info and tips.
I am going to get the indoor HDTV antenna from the site recommended by Digi
All the towers are less than 20 miles away in my area.
Hope this helps.