Once you know the engine, consult a repair manual specific to your year and engine for the precise location. A Haynes or Chilton manual will be very helpful.
Generally, the PCV valve is located on or near the valve cover(s). It's usually a small, plastic or metal valve with a hose connected to it. It might be hard to see without removing some components, especially in tighter engine bays.
In short: You MUST identify your engine type first. Then, use a repair manual for precise location information.