@rytech,
I have made similar system by using a pic. I explain you how it can be done.
The components;
1 pce. LM358 opamp
2 pcs. res. 1K 1/8 watt
1 pce res. 0R1 (0,1 Ohm) 5 watt or bigger.
1 pce. res. 6k8 1/8 watt.
1 pce variable trimpot 4k7

The schema can be loaded from following link.

http://rapidshare.de/files/10143993/ampoku.EMF.html

The output of the LM358 will be connected to ADC input of the pic.
The max. current which is the total capacity of your power supply, will be regulated by 4K7 trimpot. This circuit is arranged for measuring max. 5A current.
You can connect one ammeter serially to the circuit and connect also one current source (can be one auto-lamp) and regulate the total current by trimpot.

ERO