Order new shelves from a KitchenAid parts distributor. You can access these vendors online or through your local KitchenAid dealer. Know the model number of your refrigerator before beginning your search.
You should not need many tools, if any, for the installation. Your KitchenAid freezer should be equipped with shelf hooks on either side of the freezer walls. If your freezer does not have hooks, you may need to install them using a screwdriver and the hardware used for the freezer shelf.
The KitchenAid shelves will have built-in hooks at the back of the shelf. These are curved and sturdy and will fit into slots that are already punched into the back of your freezer wall. Simply slip those hooks into the slots. Press down firmly on the shelf to make sure that it is securely in place.
Some KitchenAid freezers have shelf-trays in them. These parts hook onto a tray hardware piece that will be on one side of the freezer wall. Simply slide the shelf-tray into place along the hardware tray.