Where can you get a red tailed hawk?

You have to go through training and obtain a falconer's license before you even think about it. They're not just exotic pets, they're amazing creatures that can't be just a house pet. Get in touch with a falconer and take some classes. If you're still interested, that person will point you in the right direction. Other than that...without a license, it's HIGHLY illegal.

As an adition to the responce above after you have your falconer's licence you are allowed to catch your own.

You can get them from a nest.