The water pump in my Holden Astra has failed and now the engine sounds like shaking a bag of spanners when it starts. I have not driven the car since this happened as I am unsure as to what harm this will do. Can it be driven to the nearest garage and roughly, how much to change the water pump?
Whatever you do, don't drive it, don't even start it. It's likely that you have done serious internal damage already and driving it, starting it even, would only damage it further. Have it towed to a mechanic and have the engine checked. I fear the damage extends well beyond the water pump.