Thanks to the great info in this thread, I just finished installing the factory fog lights in my '07 Corolla CE (NUMMI built, Southeast Toyota Dist). I just got my turn-signal switch and relay from Sparks Toyota and got it installed in about 10 minutes, and there is light! Now to aim them properly...
I got the light assemblies on
ebay, genuine Toyota (although used), under $100 for both, in great shape.
If it helps, when looking for the wiring, reach from behind the bumper and pop the fog light blank plate off and shine a flashlight in there. On the passenger side, the 9006 plug is very obvious, almost up against the white plastic of the washer fluid container, taped along with another miscellaneous connector along the support that Phil talks about. The one on the drivers side blends in with the darker materials of the support, etc.
Thanks again!