The easiest thing to do is use one of the software programs for the GRE and download the information on STARS directly from RadioReference. Then load that in your scanner.
What 700 MHz system are you talking about? Do you mean the 700 MHz STARS uses for Digital Vehicle Repeater System (DVRS)? If so that is only used for the troopers portables so they can talk back through their cars on the main STARS system. It is fairly short range; you would have to be close to a trooper using it to hear anything.
John