choose a car and customize a car(Main Menu}

i have a car racing game and i want to be able to pick different cars and the menu and levels and be able to customize cars before they go into the level so can anyone help me out with that??

Create a new scene with a selection of cars in it, use a raycast from the mouse to select a car and save its id in a script with do not destroy on load on it, load the track scene and use the data from the script to spawn the correct car. You could do it all in one scene if you really wanted.

Clickable objects: http://answers.unity3d.com/questions/4840/making-an-object-clickable

Keeping objects between scenes (saving scores or options): http://unity3d.com/support/documentation/ScriptReference/Object.DontDestroyOnLoad.html

Save what car you picked as a variable and then instantiate it from a prefab when you load the next scene.