ahh, the pictures speak a thousand words! literally! lol
i go arduino > led > led > led > built in resistor > uln2803 [[>]] arduino
with the common ground from the uln2803 to ground
but then with the 12v attached to ANY one of the [[>]] pins... it doesn't matter which one... 
also, if i ground the arduino to the 12v gnd, then it stops working.