Fog Light problem

I have a 2001 Corolla S, and i'm having a problem with one of the fog lights. A couple of weeks ago me driver's side fog light went out, I gave it a tap and it came back on. It recently went out again but it won't come back on. I removed the fog light and and hooked it up to the passenger side but it still didn't work, so i know it's not the wiring to the lamp. I can't seem it open up the lamp to see if the bulb is loose or burnt out. I doubt it's burned out otherwise it would'nt have come back on when I tapped it. Can anybody give me any advice on what it could be or mabye tell me how I can get to the bulb. I Really don't want to take it to the dealership if it can be fixed easily. Thanks in advance.