To be certain, you should:
1. Consult a repair manual: A Haynes or Chilton manual specific to your 2000 Firebird will show a diagram with the PCV valve clearly labeled.
2. Use an online parts diagram: Websites selling auto parts (like AutoZone, Advance Auto Parts, etc.) often have diagrams of engine components you can search by your vehicle's year, make, and model. Look for the diagram of the valve cover.
Using a combination of these resources will give you the most accurate location. Remember to be careful when working near hot engine components.