My mom needs a wheelchair when we get to the airport. We are flying Southwest and it is indicated on her ticket. Where do we get the wheelchair from?

The wheelchair should be waiting for your mom after the plane landed. I think you should reconfirm with the airline directly.

It should be waiting for you outside. Once the planes land wheel chair assist personnel will take care of you. Please reconfirm with you airline

You should reconfirm with the airline. I think every airline have wheelchair facility