It is true that you receive the actual activated AP at either of the two stores at Orlando International Airport. They are both directly connected to Disney's ATS computer system.
There are two stores where you can purchase your passes in the airport. Disney's Flights Fantastic is located in the B airside terminal (the one where the boarding gates are). If your airline comes in anywhere in the B terminal (Gates 60-99) you will walk right past it just before you board the shuttle for the main terminal.
If you arrive on the A side (gates 1-59), then you will find the other store, The Magic of Disney, in the main terminal right after you get off the shuttle from the gates.
Either way, you will come to the stores before you go to the luggage area where the towncar drivers are waiting.
HTH