I always remembered it as John the Leprechaun on In Living Color:

John, John, the Leprechaun
He looked for his gold, but it was gone
He looked up high, and he looked down low
He looked in the street and... OH NO!
He got hit by a truck and he was lying on his side
A fat man molested him and he died, That's IT!

I don't know if those are the real lyrics or just how I remember it but I do remember the last line word for word.