Where is my canister purge valve?

I drive a 1996 Buick regal custom 3.8L. The other day my service engine light came on so I took the vehicle to Auto Zone and had them read the code. The code was p0441: emission control system incorrect purge flow. The guy ordered me a new canister purge valve, but I can not find where the little ****** is in my car. I bought a haynes repair manual for my model vehicle and it said that for some model cars the valve is in the canister itself, but it just doesn't seem like it could fit. I know that the canister is in the rear of the car, behind the left tire, but I don't know where this valve is, any help would be appreciated. *this isn't the same as the purge solenoid mounted near the intake manifold*