Chrysler neon 2000 mk2 over cooling, rad fan coming on from cold start?

I have a 2.0 lx 16v, A/C Chrysler neon 2000 mk2 (same as dodge & Plymouth neon mk2) its over cooling, rad fan coming on from cold start and cutting in far to often regardless of A/C on or off, the A/C blows ice cold, no warm air from cabin blower, and the dash temp guage never quite reaches the optimum temp it sits quarter way up the dial just above engine cold, Where should I begin, the A/C compressor or coolant temp sensor, the coolant levels seem fine and haven't dropped at all in the last year, and the fuel consumptionn seems higher than is should be, its driving me mad and I dont want to go wasting money on parts I don't need can anyone help?
thanks for the advice guys, prob is that the fan is on almost all the time and Im pretty sure that is whats keeping the temp down, I had a bad thermostat in the past and the fan didn't stay on though! thanks for everyones comments
I'm guessing the ECU Temp sensor is to blame, is there a way of testing this or will pulling the plug off the sensor tell me anything, and where is is located if anyone knows these engines? thx