[karlcswanson]

I think the arduino is easy enough for beginers, but its also expandable for more complex things. I took this example right from arduino's reference page. This example does exactly what i think your trying to do, read a pot and generate a pwm. I remember seeing a shield and an arduino clone that provided the standard 3 pin header like the ones found in the control system, but I don't know where to find them.

int ledPin = 9;      // LED connected to digital pin 9
int analogPin = 3;   // potentiometer connected to analog pin 3
int val = 0;         // variable to store the read value

void setup()
{
  pinMode(ledPin, OUTPUT);   // sets the pin as output
}

void loop()
{
  val = analogRead(analogPin);   // read the input pin
  analogWrite(ledPin, val / 4);  // analogRead values go from 0 to 1023, analogWrite values from 0 to 255
}