FYI in case this ever comes up in a search for anyone.
I was back in AC over the weekend and used the Tropiano Airport Shuttle (1-800-559-2040). It was a pretty painless process. I called the night before and made a reservation. After I picked up my baggage, I went to the ground transportation counter, told them I was waiting on Tropiano. They gave me a ticket number and a courtesy phone to call Tropiano. The dispatcher told me they were waiting for another passenger. I had to wait about 30 minutes and my car showed up. The other passenger didn't show, so I got a ride from PHL, dropped off at my hotel (Bally's), in a new Lincoln Town Car for $45 + tip. Pretty good except for the wait, but much cheaper than actually hiring a car. They also have shuttle buses they run.
At the airport I saw the numbers for 2 other AC shuttle services that had posted prices less than $45.
AAA Airport 1 Direct and Rapid Rover were both posted at $5-8 less than Tropiano.