Most oven model numbers are located on the frame behind the main oven door.
Next, check the sides of the door and the inside near the hinges
No luck? Try behind any other doors, such as the flap at the very base of the front of your cooker, under the main oven door.
If you've checked all of the above, try the back and side panels. Unfortunately, you may have to shift your cooker to see back there.