You'll most likely have to get them from Ford, and will cost you a pretty penny. You'll also have to get the trim bezels that fit inside the fog light hole, the lower "valence" (lip), the inner parts that come with a Mach 1 grill delete (if you don't already have one installed), and a few other miscellaneous parts.
You will also have to change your hood, assuming your putting it on a GT. If you don't there is like a 1" gap around the head lights and it looks funny.
that's where i bought mine from. I didn't get it painted though. I had my local body shop do it so they could blend the color down into the car incase any fading took place on the factory paint.
I think the bumper + accessories from Ford ran me ~$600. Then paint was like $350? Worth it though. Turns heads as it doesn't just look like every other GT rolling around on the street.