Is there a special maintenance mechanics use to find oil leaks?

I recently went to Jiffy Lube for an oil change and they told me that there was oil leaking everywhere from the bottom. So I decided to try and find the leakage, however, I don't know if there's a special maintenance that is required. If so, can anyone tell me the name and the estimated cost? Oh and its a 2000 Mitsubishi Diamante.