Are you using a UNO or Mega? I've done it with 2 PWM motors and 1 regular on/off motor. The range is however far the controller can go, that's it.
The schematics you can find online, in fact that site shows you how to wire it . As for the code, I can give you a sample, that works for the ps2x library that I have. It will only work if you and I have the same library, otherwise your going to have errors.
Ok, we'll I'm not home right now, but I send it to you later.