...heating inside blows cold and there is? no water going through the tubes from the radiator to the engine. From what i have read it could be the head gasket but im not entirely sure as there are not many if any of the tell tale signs ie. there is only a little smoke from the exhaust (and only when engine first starts), no white gunky stuff under oil cap and the coolant is the right colour. I have changed the thermostat, the radiator and have changed the oil. The only thing left from what i can gather is the water pump but have absolutely no idea where i can find this on the car or if i should even attempt it being a total novice. If anyone could please help me as to what else i could try and where i can find the water pump i would be very gratefull.
cheers
dan

It sounds like you have an air pocket inside the engine. The air must be removed or you will have hot spots. On BMWs there is a vent at the front of the engine that can let the air escape. You need to open the vent screw, let out any air until a little coolant starts to escape. Close the vent. Refill the plastic reservoir tank to the midway "FULL" line. Shut off the engine if the temp. goes beyond midway on the instrument panel. Look for the water pump close to the radiator. It will have at least one belt around it. Check to see that the belt is there and fairly snug. Do not overtighten. The coolant doesn't circulate if there is a loose or broken belt. Keep doing the air bleed project until all the air is purged from the system. Check or replace the reservoir pressure cap with a good or new 14psi or 15psi cap.

sounds like the theromstat is stuck
I have bought a new one before and it was stuck
didnt know until i put it in though
malfunction
test
take the thrmostat completly out and see if it helps
if it does than either a you got a bad thermostator it isn't installed right

does sound like a water pump...if there iss no flow the the shaft probly broke...go to autozone.com...sometimes they have "how to..." on most make and models...forgien model car are very expensive ...you can try getting a used part at usedparts.com ....i have had good luck at both site....wish i could help more