I believe that the IRS has tightened its rules regarding indpendent contractors. You should check with your accountant or attorney to be sure.
No matter what "contract" from you use, many states will look through the contract to the facts of the employment (what is actually going on) to determine whether one is an indpendent contractor or just an employee. Therefore, whether its tax treatment or liability concerns, a contract alone will probably not be sufficient to avoid adverse consequences, if the facts show different -- If you know what I mean.
Heres a reup as promised. I agree with QueEx. You want to consult with your attorney/ cpa to make sure you have your bases covered. The kit has some good templates to work from. Peace.