Hate to say it, but you're NEVER be able to do what you want to do without learning and dealing with at least a LITTLE of that stuff....
There are TONS of motor controllers out there, but you have to understand at least a little of the electronics to know how to go about hooking them up and controlling them from the RPi.
For instance, you need to know about the input Voltage that the controller board requires, the max power input it can handle for the motors, and the max current draw it can handle FROM the motors.
Personally, I use a lot of pololu micro gear motors (I tend to prefer the high current ones for my applications) - www.pololu.com
For some of my bots, I use this controller board, which works well with the motors above: http://www.pololu.com/catalog/product/713
. However, I don't know if that works with the RPi. It requires 5V on the control pins (doesn't the Rpi give 3.3V on it's GPIO?) It also requires PWM signals to drive things.
So as you can see, you need to be at least generally aware of the power stuff.
But like you, I don't like when it gets down into needing to figure out what size resistor to put where and when do you need a capacitor or a diode, etc. Analog stuff like that drives me crazy. If you mostly want to just deal with hooking up sensors, reading values, and then commanding motors, I'd suggest sticking with Arduino based stuff - the Rpi is serious overkill for simple robots...