Fog lights are for lighting a small area in front and off to the sides to see the edges of the roadway while driving in FOG. For your application some bright floody off road lights is what you want, and yes down on the bumper. If you need to light up further out in front is when you would go for the spot type driving/off road lights either on the bumper or windshield.
There are tons of them out there. Jeep Auxiliary Lighting - Quadratec
is a good place to look as they have all kinds on their site. You can see what is available in your price range.