I am having trouble trying to figure out where to start writing a physics of a car , i am currently working on a racing game so for that i need help from where to start writing the physics of the car . Any book recommended etc.

If you don't know where to start then you're not ready to do it

You'll need some strong understanding of basic Newtonian physics wrt rigid bodies. Physics for Game Developers by By David M Bourg should point you in the right direction.
Make sure you can have a box standing on four springs on a flat plane, that'll be your starting point.

If you want to get serious at car physics modelling, start from the basics:

Race Car Vehicle Dynamics by Milliken is considered the starting point for vehicle dynamics applied to racing.
Tire And Vehicle Dynamics by Pacejka for tyre modeling ( this is going to be the most important part of the whole simulation)

But if you want to do a burnout hacky basic arcadey thing, just use some of the prepacked "vehicles" available in PhysX, Havok or Bullet and save yourself years of work.

I'm also working on a 2D racing game, but not started the physics yet.
I've found this 2D car physics tutorial: http://www.gamedev.net/topic/470497-2d-car-physics-tutorial/
I think it's explained simple and much sorter than reading an entire book. Only misses the skidding of the car when you brake too hard or accerelate too suddenly. Thouse should be solved easily by limiting how much force can your tire take from or apply to the road. Also when braking and the tire stops rolling but the car is still moving, this limit should decrease.
I have been also thinking if it's easier learning how to use an existing physics engine (there are many free 2D engines in C++) or creating one yourself. I found this tutorial to be the easiest and you understand better what you are doing.

hmm thnx both of u , btw i am making 3d we look the stuff u guys posted thnx again