Huge oil leak under car (Honda Accord EX 91 M/T)?

I walked out today and happened to see a huge spill of oil under the car. I checked under, the area seemed to be under where the oil pan was. There was what I thought a leak where the bolt was, since I was able to wipe oil off from under it and some more accumulated thereafter. Before adding oil, I checked the level and everything was fine! Just in case the dipstick was lying, I added half a quart and the level had increased, as partaken from the dipstick.

What might be leaking instead? The car was able to turn on normally, gears shifted easy as well as no ringing nor odd sounds as if a car was out of oil. The transmission oil bolts were clean and tight.

I'd like to be able to do this myself, mostly for money reasons, but I need to know where to look because I don't own more than one jack stand currently.
Also to give an idea of how much oil is spilled under the car, imagine a child with a full glass of milk and that child dropped it on the kitchen floor.

You might just have a very small leek, as you found just a drip on the oil pan.
Someone else might have parked with a bad leek before you parked in that same spot.
But what concerns me more is that you added more oil to a full oil pan. You should never fill it past the top indicator line. Now you should drain some oil out (a hard job to do without loosing too much oil.)
Check and top off all of your fluids and park in a clean spot. Check back in an hour or so and see if there's some sort of spill.