oil dipstick - think l have overfilled my car with oil?

For checking engine oil level yes, all cars have this. But where yours is located? l have no idea.

yes,
it should be on the engine block somewhere, what u could do is jack up the car, put a spare wheel under it, so that if it falls it doesnt kill you.
wait till car has not been used for at least an hour, so the oil is cold.
then look for a a big nut (sump plug) sticking out of the sump. (large flat square thing), this will have a square shape
get a big tray or bucket that will fit under the sump lug. put it under the plug.
get a sump plug spanner or an adjustable spanner . undo the plug/nut.
oil will drip out into tray/bucket, it will come quick so watch out.
let all the oil pour out.this could take an hour.
when it stops coming out, re fit the sump plug, do it up tightly, but not too tight. becareful not to thread it, (screw it in sideways) as then it will be no good. so dont do it.
once sump plug is back in. get new oil & refill to required amount.
keep old oil for cleaning engine parts.

otherwise u could get problems,as the engine would be under too much pressure.

Yes, there is. Did you have one when you bought it? Did you ever check? Did someone use it and not put it back? Or, is the dipstick the owner?

Assuming your car is a 16v model, the dip stick is located quite low on the front of the engine near the back of the radiator.

in response to 'jay.'

the reason the oil is taking so long to drain out your car is becasue you are letting it cool down. do it when the oil is warm and it wont take so long. it wont be as thick when warm.