If you're looking for a long range indoor HDTV antenna you need one that has a range of between 80 to 100 miles.
80 to 100 miles is the longest range that most indoor antennas can get for most of the cheaper ones.
But if you need one that will reach a longer distance you can get the Skywire Antenna that has a 960 mile range and is an indoor TV antenna which is also very cheap and works well for $10.00 at Walmart.
If you really need a longer range antenna your best thing to do is get an outdoor antenna if you can put an outdoor antenna up because it will extend the range and you can pick up more channels from farther away.
The outdoor antennas will pick up signals much better and give you the best picture quality.