Best way to locate leaks is honestly to let the pros do it - they inject a UV dye into the system and then use a black light to locate the leak. Most commonly, the compressor shaft seal leaks - especially if it doesn't get used often; makes the seal dry out over time. But there is a possibility that the leak is somewhere else, so I would be hesitant to just say replace the compressor.

You can buy the dye kit and do it yourself, but it's a bit messy, and you'll likely end up with alien-green dye everywhere.

Norwalk? Small? - Hah! - Belpre's about half the size; and you guys at least have the racetrack (although I missed the last 2 years due to extenuating circumstances). Unfortunately, you're 3-4 hours away, so we'll have to resort to long distance troubleshooting.