Reprograming ignition key and tumbler

I replaced an ignition tumbler in my 1999 Toyota Avalon XLS. The old tumbler did not pass beyond accessory, which in turn could not start the car. I replaced the tumbler bought from the Dealer. Now it will not start. I believe the Avalon has a computer transponder and it has to be reprogramed. Now, how do I reprogram the key, tumbler the to the computer?