Replace or repair fuel pump

Where is the best place to go online and buy the fuel pump?

I didn't check the fuel pressure this car don't have a fuel pressure test port and the tester that I have it fit a test port, on this car look like I have to disconnect the fuel line and connect a fuel pressure test to the fuel line. When I turn the key to run I don't hear the fuel pump relay click and I use a test light and check for power at the relay and there is no power, I can take the fuel pump relay out and turn the key to run the fuel pump will run and want cut of until I turn the key of the engine starts but stop immediately when the engine stop I can hear the fuel pump run for a few second and cut of can you explain to me what is happen why it no power at the fuel pump relay and what turn the relay on and the fuel pump and what keep the fuel pump running?

Is this the procedure I use to reset the security system
TOYOTA LEXUS IMMOBILIZER RESET
We called the dealer here is their response: Lock the car and shut all doors, then use the key to unlock the driver's door. Push and hold down the panic button on the remote. With no one in the car lock and unlock the car using the key remote. Disconnect the battery and reconnect as a last resort.

I did the reset test on the security system it didn't help my problem the car is still doing the same thing I need to know why I don't hear the fuel pump relay click when I turn the key to on what I need to check? But if the fuel pump don't run when I turn the key to run I wan't be able to check the fuel pressure I believe the fuel pump suppose to run for about 2 seconds but it not coming on when turn the key on why?

Where is the relay located? I'm not sure I have located it the relay I though that was it I switch relay that didn't help do the relay suppose to click when I turn the key on or do it click when the engine is cranking? The relay I thought was it I remove that one and turn the key to on I can hear the fuel pump run but when I put that relay back in the fuel pump want run I don't understand that.