Depending on the way that your steering is set up, you may be able to attatch a potentiometer to the steering axel, I guess it would be. Then it would be a simple matter of plugging into an analog port and getting the feeback.
Other than that I don't know of any other sensors you might be able to use like that.
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My daily diet consists of: brackets for breakfast, pneumatics for lunch, software for dinner, and plastic tubes for dessert.