The stall current is actually the most important metric, so if you could find that, too, that'd help you find the right driver!
Do you have a torque sensor of any kind? If not, you probably will not be able to reach 100% closed-loop torque control.
If you want to emulate torque control with current draw, there are a number of controllers that read current consumption that you can build a rough control loop on top of, such as the RoboClaw 2x5A from Orion Robotics. You'd also need a microcontroller to continually read the current and adjust the duty cycle.
Other options include using a plain PWM DC motor controller, and a current sensor such as the ACS series. Pololu has some:http://www.pololu.com/product/1212
(3A may be less than your stall current, so you may need something beefier)http://www.pololu.com/product/1185
(sensor only, needs driver)
The "torque control" drivers that I know of typically come in factory motion control systems, are expensive, and require specific motors/sensors to work.