Skyline,
I recommend doing as much information gathering as you can. There are 34.7 places the Boxster engine can leak oil. They range from a $2 fix to a new block. I would recommend buying some engine degreaser (or any degreaser) from your friendly auto parts store. Take both rear tires off, and both wheel well plastics off [ 20-30min of work, not much time ]. Then also open the engine access from the top [ Pedro has a how-to on this [
www.pedrosgarage.com] ] 10min job.
1. Before cleaning, inspect the engine as good as you can from the top, and each wheel well. Take images with your digital camera. Try and find the leak and photograph it. Dont use your phones camera, it sux.
2. Clean up the engine with the engine cleaner / degreaser. follow the directions, use sparingly, rinse and repeat.
3. Run the engine for 10min or so, revving up a few times. Make sure your car is on jack stands and secure. ZERO ACCIDENTS please.
4. Reinspect for leaks, if you see anything that looks like a leak, please photograph it.
5. You may not find the leak in step [ 4 ], you may have to drive it for a week or two for the leak to show itself. Thats ok. Just repeat this procedure after a week or two.
You will only need to invest 1-2 hours total, and you will have a clean engine bay either way.
Post images of the leak when you find it and also describe where the leak is and the board will gladly discuss your options and estimate repair costs.
*Check your oil level frequently, you dont want to run out of oil!