I applied through an employee referral. The process took 1 day. I interviewed at AT&T (Saco, ME) in Jun 2009
Interview
In order to get in the door you need to know someone, random candidates rarely are accepted. I had communication with an employee who was a vendor going from business to business, he became a store manager and recruited me. I then was called by the hiring manager, was offered an interview, interviewed, then was sent for a 4 week training class out of state. All expenses were paid.
It is a basic customer service and teamwork questions. Asks you to teach them how to do something you're passionate about. Nothing crazy or unexpected. Laid back but professional, answered all my questions as well.
After the initial interview, the store will likely assess your product knowledge. They may ask you about various cell phone models, features, or accessories, and how you would explain them to customers. This is to evaluate your ability to understand and communicate technical information.
Interview itself is pretty easy. The two times I've interviewed with them as varied based on the manager, but they're pretty forthright with everything they're telling you and the expectations of the job.