Where is the smog pump located on my 2011 Toyota Tundra 4.6 L ?

First: A "code book" should prompt diagnostic process and testing, not component replacement. It's not accurate. You can have a problem with the air pump. You can have a problem with the air pump drive circuit. You can have an issue with the air injection control driver. What testing has been performed? As for location of the pump and how to repair it, just obtain a repair manual. We can't get into that in this forum.

PO418 is related to the air injection pump control circuit - not the pump itself. Pump is physically located under the intake manifold - which will require removal. Disregard information in your “code book” and seek *hands-on* assistance from local auto repair facility.