yes, you can by calling the call center but they are sooo soo much more. i would just get a "pay as you go" phone and pay the 35 bucks for a month then not get another pay card.
and yes, you can get a pretty nice pay as you go phone. like the G1. I have the cliq and LOVE IT!
P.S, you can buy the phone from the company its self and they are most the time unlocked. try looking up HTC for G1