To make a long story short, my car didn't come with a front plate, so I needed to put one on. Didn't get the stock bracket with it, either.
I ended up finding a post that suggested looking into brackets from Skene Design. (skenedesi g n. c o m) These brackets mount to a horizontal part of the front bumper and still require holes to be drilled, BUT they won't be visible if you decide to take the brackets off. Anyway, thought I'd give a revival to this thread as it's relevant to the 2011+ models, specifically.
Mounting location options (if you want the plate centered) are:
Very bottom edge of bumper, below the lower grill, but you'll have to deal with the pointed shape of the bumper there.
or, underside of top edge of lower grill (approximately where the stock bracket would cover) which is about 1" deep before you run into the grill itself. The main issue I ran into was getting access with a drill to put in the pilot holes for
Bracket size options are 0.5" or 1.5" - I went with 1.5" just because I wanted to make sure I had clearance, but 0.5" might work.
The only real issue that I ran into was getting a drill into that area to drill the pilot holes. Quick tip: Remove plate and move the slotted brackets all the way up and out of the way to give you more room to work with, and you'll probably have to drill at a bit of an angle, no matter what. After that, you can use a very small screw driver, or just screw them in at an angle, then measure and re-adjust the brackets to the desired location and put the plate back on.
If you're not worried about scraping the bracket by mounting it to the bottom side of the bumper, you could probably bend your plate to the contour of the bumper, then mount the brackets so that they are angled to fit the bent plate, or you could mount it off to the side.
Here are some pics of the finished product:
Maybe sometime I'll find time to get a better "true" side shot, rather than one that's angled from above. But, as you can see, the brackets do stick out a bit, but you can't tell unless you really look for them, and it looks pretty clean from the front. I had thought about painting them black, but ultimately I was just too lazy. I will probably either raise this so that it's just under the pointed part of the bumper, or lower it to cover more of the lower grill. When I mounted it, I just wanted to get it on so that I didn't get a ticket.