For brand new heavy duty trucks, try Heavy Duty Trucks USA. Trucks Junction and 1 Used Trucks both sell used heavy duty trucks online for a cheaper alternative.
If you look hard enough you can always find a good deal on heavy duty trucks. At the same time a lot of dealers offer waranties with their trucks for a little more price, it all depends on how much you want to spend.
I would advise you to check out Commercial Truck Trader. They offer listings for new and use heavy duty big sleeper trucks, along with light and medium duty trucks. They currently have over 62,000 trucks listed for sale! Check it out at: http://www.commercialtrucktrader.com/
You can find heavy trucks anywhere from searching online to going into a car dealership/shop itself and looking around at different heavy trucks that they have available.
There are many different places to purchase used vehicles. Whether they be cars, trucks or heavy machinery, like dump trucks, they are easy to find on Craigslist.
You can find some good heavy duty platform trucks on either Ebay, or craigs list. If you know of any auctions, or swap meets that are close to your house, I would suggest that you try one of those.
Depending on the types of trucks you are looking for, you can find trucks at http://www.penskeusedtrucks.com/. You can also find trucks at http://www.buyatruck.net/
A Duramax Diesel is the much successful line of diesel engines produced from General Motors. You can find these engines in the GMC Heavy-Duty trucks and the Chevrolet Heavy-Duty trucks. Duramax is the second-best selling diesel engine on the market behind Powerstroke from Ford. The current Duramax diesel is a 6.6L V8 that produces 365 horsepower and 665 pound feet of torque.
Freightliner is used for heavy duty trucks such as semis. They carry a lot of weight without too much strain. To get one you can go to Freightliner.com and find just what you are looking for.
Heavy box trucks can be found in used car lots in rural areas. Also many manufactures like Ford carry a line of heavy box trucks for use on farms. Checking you local truck dealers will be the best way to find these trucks.
One can find military trucks for sale on site such as eBay. One can also find military trucks for sale on Military Trucks, TNJ Murray and many other places.
There are lots of places online where someone can find old trucks for sale. Some of these sites are: FossilCars, U-Haul, carsforsale, Autotrader and Trucks for a Grand.
One can find mining trucks for sale at a variety of different truck dealerships. Some of the places that one can can find mining trucks for sale are: Rock and Dirt, Siemens, and Chevy.