Random idea, normally provider's GPRS networks are NAT'd off from the outside world, so you'd obviously need your providers help with this one.

They shouldn't have a problem tracking the IMEI, and seeing what tower it is connected to, and if there is an ongoing GPRS session (more than likely). Then provided you had SSH installed on your phone, speak to the right people, SSH into your phone, and run a few commands taking pictures, scanning for wifi networks, and getting the GPS co-ordinates.