well there are two oilpan bolts. one is in the middle rear (towards the back of the car) and the other is in the middle front (next to the steering bar) and it's very difficult to remove. hopefully that will clear the confusion. thanks!
If it is on there pretty good, I just use a normal box-end wrench and tap the end of it with a rubber mallet. I am assuming you have the car sitting on the ground when changing the oil, and yes, that would be an ackward angle to get at that bolt if you are lying on the ground. The rubber mallet trick should work.
Can you get a grip on it with some long handled vice grips, you also might try the size smaller than it should be and tap it on there and use that. You will want to replace the bolt anyways.
If need be I think they make some socket wrench's that are meant for stripped bolts at your local parts stores or at Sears...