Bought my kit from VAG Parts. Although the kit advertised is for the pre facelift cars, they also do a kit for the post facelift cars if you ask. From memory this was around £150 -ish! Then bought standard foglight loom from Halfords, some plugs from Audi. After some solder and a roll of looming tape, you've got a full, standard looking set up.
I didn't bother with the new OE switch as this would be another £50, so I just put a small, normal switch, hidden from view, in the cubby hole on the right of the steering wheel. When the fog lights are not on, you cant tell there is a switch there, when you turn them on, the cubby glows red becuase of the led in the switch.
Was really easy to do, the hardest part was routing the wire in through the bulkhead, but even that only took 30 mins.