However, without seeing the specific engine, pinpointing its exact location requires a visual inspection. A repair manual specific to your year and engine is the best resource for an exact diagram and location. You can also find diagrams online by searching for "2000 Toyota Camry 1MZ-FE EGR valve location".
Caution: Working on the EGR system can be messy due to carbon buildup. Be prepared for potential cleaning or replacement.