In doing some research on the net, I came across a website with a lot of info on headlight/Fog light bulbs. It's at bestheadlightbulbs.com. It does not cover aftermarket lights that you add to your vehicle such as Rigid, Hella, Baja Designs, etc.. It has info, reviews, buyers guide, tests and comparisons on replacement and upgrade bulbs for Headlights, Fog lights, Interior lights and license light bulbs. Also has info on Projector vs. reflector, Kelvin, brightness, etc.. It covers Halogen, HID and LED.