Most tire companies only sell their own tires new because that is where they make the money. It is possible to try the local car showroom however because if they do second hand cars they may also sell second hand tires.
Good year company
Discount Tire/Americas Tire
Cooper tires sells various brands and there prices range depending on what company you buy it through.
Almost every tire store sells reasonable used tires.
Anyplace that sells Medalist tires.
Maxxis, Dunlop, Metzeler, Michelin, Bridgestone, Pirelli to name a few
Dynamic Tire Co. sells Sailun tires through subsidiary Husky Tire and Mustang Tire in the US.
To find a company that sells Hercules tires near or in Pittsburgh, first try yellow pages online. This will give you a list of companies in that area. Another option is to go to the Hercules tire website and search for the appropriate location.
One can purchase 205 45 17 tires by going to a Firestone store. The Firestone company sells a number of tires for different automobiles, including 205 45 17 tires.
Michelin is a company that sells many different types of tires, so you should be able to easily order the tires you need. Otherwise, you can purchase Goodyear tires, which also have a good reputation.
Almost every company makes 'rain tires' -
Discount Tire Direct sells discount tires and they offer free shipping. The site is easily found by typing the keywords into Google.com. The website for this company is easy to navigate and the offer for the free shipping is right on the home page.