Below are a few DSLR Cameras, telephoto lenses, wide-angled lenses, and accessories which are available at Amazon.
For Air Show photography it is recommended to get a Digital SLR Camera along with a telephoto lens for aircraft displaying in the air, and a wide-angled lens for aircraft on static display.
A camera bag will also be needed to carry your expensive camera equipment around with you. Ideally it should be rugged enough and padded well to protect your camera & lenses, and be waterproof. A backpack can be comfortable to carry or a wheeled-bag is very useful if you don't want to carry your heavy camera equipment.
You will really appreciate a fold-up chair instead of having to stand up all day or having to sit on the ground.
More information can be found at Canon Digital SLR Camera & Lens for Airshows.