In Canada, the site Farming Equipment Canada is the best resource to find information on purchasing tractor tires. In the United States, sites like Wise Geek are great resources for gathering information on how to go about buying these tires.
Tractor tires take alot of wear and tear so you want to find the most durable for the money. I would also consider buying your tractor tires with a warranty.
One can find information on buying wheels and tires at your local tire dealer, such as Goodyear, or Bridgestone. They offer the most comprehensive up to date information, so it is best to deal with them.
Tractor tires, depending on what you are buying, can cost anywhere from $300.00 all the way up to $2,500.00 or even more. You may be able to find better deals if you search, but it's more than likely that to buy good tractor tires you'll have to pay a bit more.
You can find tires for a John Deere tractor at Lowes, Home Depot, Amazon.com, and ebay.com. There are many stores that currently sell John Deere tractor tires.
I was not able to find any online vendors for tractor tires that offer free shipping, but I did find information in regards to the cost of the shipping. If you check this site, it provides a lot of information as well as their shipping rates.
To find good deals for buying Goodyear Tires one can go to the discounttire site and put in the information of the car and tire that you're looking for and it will give you a local place to find your discounted tires.
Tractor Tires can be purchased at several online retailers. Examples include TireTown Farm Tires (www.tiretown.com) and Tires Unlimited (tiresunlimited.com)
American tires are more in demand when it comes to buying tires for the same reason that foreign tires aren't as reliable. In order to find only American tires, you should look at the American tire website.
There are several tire store in the area too choose from.You can find a limited selection of tires for tractor trailers in Milwaukee at Sears.
www.tiretown.com/rearfarm.htm has them. You could also try a local tractor store.
Many times you can find used tractor tires at tire business around you, I would call around first and compare prices as todays gas prices are insane, or you could always search www.ebay.com for used tractor tires.
There are many online tractor tire resellers. Most large tire manufacturers sell tractor tires. For example Firestone. You can compare prices on tractor tires at BizRate.com if you want to find the lowest price online.