Yeah, so just check the elbows first. The top one is visible to the right and a bit below the alternator. Then the second one will have to be checked with your hand since it's not visible, it's inline and to the right with the top of the power steering pump reservoir. Just stick your hand under and around it to feel for coolant. If that's not it, it's either the water pump or it's also possible it could be your LIM gaskets but you'd see that right away.
And what he said about flushing the heater core. ^ There are two hoses right behind the alternator that easily come off, flush it with some force like a garden hose, back and forward flushing.