Thank you for your question.
The most likely source of the leak is either the sump gasket, or the front or rear crank shaft seals. Ideally, if possible you should have the engine steam cleaned or jet washed from underneath, and the with the engine running, check to see where the oil is coming from. As it sounds like a bad leak, it should be fairly easy to spot.
The front crank seal is fairly difficult to replace, as it's behind the pulley and timing belt etc. the rear crank shaft seal is also difficult to replace as the gear box, clutch and flywheel will have to be removed. To replace the sump gasket, obviously the sump has to come off.
I hope this answers your question.