I am leaking coolant from my 2002 Disco II. I don't see it on the dipstick, so I am optimistic, but this could still be a pain in the ***.

Where should I look for the source of this problem?

Front cover, water pump, head gasket at the front or back edge, up at the valley gasket front or back, throttle body heater plate, expansion tank (check for cracks), check all hose connections.

A very good suggestion would be to go to Napa (call first so they can get it in from another store if necessary) and get a little bottle of coolant dye. You don't need a light as the dye is super bright.