>>8That big blotch you talked about sounds like you ruptured the LCD screen and the crystals inside it as well. Those crystals would have leaked away from the rupture and damaged the screen, so the whole LCD screen would have to be replaced most likely, along with the touch sensors if they were damaged too.
Now, I might be wrong as I don't have any Apple products at all, but I have based what I've stated from a similar thing occurring on one of my LCD monitors. I wouldn't know the cost to repair it, but it would be expensive. Unfortunately, if I am right there are no alternatives - you either pay to get it repaired, do some possibly rubbish repairs yourself, or live with it.
I will admit to doing some searching, and the best price I could find was $130 in Australia, so you are probably best to go with your $100 friend if you can trust him.