I would start looking over the radiator real close. I suspect a leak there.

Okay. The undercarriage is soaked with what appears to be oil, but my oil levels are healthy. Should I just bite the bullet and scrounge up some money and pay for somebody to take a look, or is this doable for an amateur?

I would clean up the entire underside and then watch to see what area it is specifically coming from

check your radiator for any kinds of bubbles or cracks..check your bottom radiator hose..which is on the passenger side bottom of the car..check the connection of that hose to the radiator

with the knowlegeable people here..if you pay attention anything can be done

where all here to help you...and regardless of the ammount of problems you have..we can help you fix each problem one by one...theres alot of people here who are really good with that motor of yours..myself included

Thanks much! I'm going to clean the undercarriage tonight and check it out early in the morning and let everybody know.

Yes this is doable for a amature and u will be proud of urself when u lick the problem. I suspect either a leaking radiator hose, a hole in the radiator from a kicked up rock or possibly your thermostat is bad and the coolant can be bubbling right out the overflow jug. OR could simply be a faulty radiator cap!

wipe everything down, let the car cool down, then have a buddy start it up and rev it at about 1800-2000 rpms, and look for leaks.
run ur hands along the bottom of the hoses to see if there dripping, scoot underneath the car and look where the drips are originating from.
check and see if the radiator cap is leaking while running

We will solve this

Coincidentally, my radiator went just 500 miles ago. There was a crack in the plastic behind the driver'* side inlet (or outlet?) which leaked coolant behind the radiator so you could barely tell where it was going.

I ended up replacing the radiator with a brand new one off of ebay, for $85 shipped. I was amazed at how well it fit for being an aftermarket radiator.

Dumb question, but is there an easier way to see if there is a hole in the radiator, or a smaller leak, without taking it out?

More often than not, a serious radiator leak will have the car leaving coolant drips on the floor while its running.

Where do you live btw?

One of these works well for finding leaks.

http://www.amazon.com/dp/B0002SRGWU?tag=ppl-20