We used Virgin back in March. Our 3 cats flew from Heathrow to Dulles, which may be the route you need to take as well (there are only certain cities that can handle live animals and I don't think PA has any). BUT, I vaguely recall a thread here where someone said Virgin doesn't do this to Dulles anymore. Don't take my word for it, though. You'll still need to phone Virgin. The phone number for Cargo/Live Animals in on their web site though IIRC, it is somewhat buried.
You will need to get an airline approved pet carrier (we ordered online as high street pet shops generally don't have them). You will also need to get your vet to sign off that the animal is fit to fly. Depending upon your state, you will need certain vaccinations. Maryland doesn't require rabies, but others may.
My husband handled everything himself. It's a bit of a pain, but not impossible. If he can do it, anyone can!
HTH.
