Where is Zapdos in Pokemon Yellow?

Zapdos is located in the Powerplant. You go to Cerulean City and head to the top right corner. From there you surf down until you find a large building. Go inside and Zapdos is waiting.

Zaptos in the Power Plant i think which is located right under rock tunnel and right next to Cerulean city.

Go to the power plant

(south of rock tunnel)

You can find him in the power plant, he will be level 50.