rugerdog is in the States where the controllers are very approachable and have a good attitude. I've had an approach controller begging me to shoot a practice spamcan ILS into a busier airport than LHR because he had a bit of a lull in arrivals and he was getting bored.
So rugerdog, next time you are out and about call up approach control on the radio and ask them if they have time to answer a question, then ask them when is a good time to request a T&G or a full stop/taxi back. Or call them up by phone and ask if you can go look around, they are very happy to let you watch them at work.
It's not getting in that's the problem, it's getting out. You can easily end up being "number 21 for departure" and that costs a fair bit of money if you are paying on the Hobbs.