Wilsons Sandbox

I seem to have a coolent leak. I am collecting water spots down the right side of the engine. It doesn't leak when I look at it so I guess I'm asking - where's the most likely place to start? The recovery bottle isn't at the full line (it's maybe a 1/4" down from full. All hoses seem to be tight. I'm leaning toward the cap on the recovery bottle but the water level shouldn't get up to there....