Clark Stoeckley, the artist behind the WikiLeaks Truck, makes these decals and sells them. If you send him your car's picture he'll even design a custom wrap for it if you want. He doesn't, as far as I know, check Anon cred before selling them.
I was looking into it to make a WikiLeaks Cavalry outfit for my friend and her horse, but it didn't work out for various reasons.
I'm shocked that it isn't covered in hashtags
I was at the National Mall 2 weeks ago. There were some protesters marching in regards to immigration reform. This van was parked near them and kept following the protesters to the Freedom Plaza. (Is it freedom plaza or Freedom Square? I can't remember, I saw so many sites that day, FYI Museum of Air Space was my personal favorite!!!)
I approached the van and knocked on the door, the woman driving it ignored me. I just shrugged my shoulders and kept on. It was the Guy Faux mask that drew me to it.