Car manufacturers generally list the turning circle radius, as well as the wheelbase of the car. From there following the diagram above with some simple maths you can calculate back to the approximate steering angle of the inner wheel.
atan(wheelbase / (turning circle - car width)) = angle. For the outer wheel don't subtract the width.
Picking a random car spec sheet look on page 62 of: http://www.audi.co.uk/content/dam/audi/production/PDF/PriceAndSpecGuides/ttrs.pdf
That quotes a wheelbase of 2468mm and a turning circle of 10.7m (giving a radius of 5350mm). atan(2468/(5350-1546)) is about 33 degrees.
A more extreme example from this taxi gives 53 degrees.