No, the images on the cars are not made in Photoshop. The is an informative post on how I use Photoshop to assist me in making designs. There are alot of pictures and words to follow. Ok, here goes.
Step one:
Find a dope picture to make a design with and open it in Photoshop. I am using Eric Estrada. Because he is the bomb. 
Step two:
Grab the infamous Mini Cooper and drop down a rough design of what you think the overall shape is of the photo you are going to use. Take a picture of it from the top looking down and upload it to this website. Save it to your desktop or where ever and open it in Photoshop. Use the "rectangular marquee" tool, or as I call it the select tool, or the dotted line thing to drag a box around the top of your car. Most of the time, I just select the roof area. Click on edit, copy. Or push CTRL C
Step 3:
Open the Eric image again and click edit, paste. Or CTRL V if you are super keyboard short cut cool.
Step 4:
You should now have an image of Eric with the mini cooper image on top, like this:
Step 5:
This is where it doesn’t hurt to have a little Photoshop experience. If you hover the mouse pointer over the top corners of the mini image that you just imported, the icon will change to a little arrow that is curved. If you don’t see that, refer to your manual and have your serial number ready when the tech support guy in India answers the phone. Or...you could click on image, rotate, free rotate layer. Either way, move it to the general area you are trying to match up. Like so. After it is in place, look for a button that says Opacity. This will make the top layer, the Mini, see through, so you can see through it. I set it on 50% because that’s how I roll.
Step F:
Now, you might say, "Hey, the Mini image is so much smaller than the image of my hero, Eric Estrada." No problem. Just look for an option to scale the top layer. Below is how I get to it. CAUTION: If you freehand resize the top layer of the Mini, meaning you click on one of the tiny boxes in the corner and drag it diagonally towards the center of the selected layer, you will run the risk of distorting it, and making your final design poo. So look for a way to resize the image equally. I just type a higher or lower number in the box and fine tune it until it is close.
If you don’t see a place to type in numbers, click on image, resize and scale. Then it should give you an area where you can put different numbers in.
Step fourteenteen:
Ok, so you have the two layers matched up as best as you can. Look around the edges and take note of where things don’t match up. You can see that I have some work to do back in the game. So get back to the roof of the mini and start moving things around.
Step threve:
You can see that I have gotten closer to the shape it needs to be in. Now for the fun part, you have to repeat this process several times until you get everything right. Once you have the basic shape, you can start filling in the details.
It is 2am here and I’m not quite sure this makes sense to everyone. If something is unclear, I will be glad to explain. Happy painting!
