Aside from the cosmetic look, most "factory fog lights" don't actually contribute to better visibility.http://www.danielsternlighting.com/tech/lights/fog_lamps/fog_lamps.html
I am not sure that you wee told correct information. It can be a bit of work to install factory fogs into their factory places using factory switches and wiring...but it usually involves finding the wiring block and plugging everything where it is supposed to go, which can be quite involved but possible.
If you are set on them, why not just get the OEM 'foglights' and wire them with an after-market harness?
09 Corolla 1.8L-370Kkms(231Kmi)-PP,Denso
05 LeSabre 3.8L-210Kkms(131Kmi)-Sopus,Wix
03 Sierra 2500 6.0L-204Kkms(127Kmi)-Sopus,Wix
All with mpg > EPA