1badgmc
I'm Awesome
do you have to get projectors or can you use the stock headlights?
You can use stock headlights, just know that they're not optimal. Also note that HID bulbs don't have painted glare tips like 9006 lowbeam halogen bulbs do and your stock headlamps aren't shielded, so you will be causing glare for other drivers. 99% of aftermarket projector lenses pretty much suck ass, so that's not an optimal route either.
The best way to do it would be to buy a set of clear headlights and then get a pair of projectors from a vehicle designed for HIDs and then retrofit those HID projectors into the clear headlights. This route is much more expensive and labor intensive, so it's just not feasible for most who want HIDs.
The compromise is to find a good set of headlights that have glare shields over the lowbeam bulb. This shield is very important to reduce dangerous glare to other drivers. There are a few different shielded headlights out there that you can buy, but from my experiences, the ONLY ones I will recommend are the TYC Elegante headlights.