Ooh i got a couple:
My friend thinks he is smart. He told me an onion is the only food that makes you cry, so I threw a coconut at his face.
A child asked his father, "How were people born?" So his father said, "Adam and Eve made babies, then their babies became adults and made babies, and so on." The child then went to his mother, asked her the same question and she told him, "We were monkeys then we evolved to become like we are now." The child ran back to his father and said, "You lied to me!" His father replied, "No, your mom was talking about her side of the family."
A man went to his lawyer and told him, "My neighbor owes me $500 and he won’t pay up. What should I do?" "Do you have any proof he owes you the money?" asked the lawyer. "Nope," replied the man. "OK, then write him a letter asking him for the $5,000 he owed you," said the lawyer. "But it's only $500," replied the man. "Precisely. That’s what he will reply and then you’ll have your proof!"
Laugh Factory is a good place to get this kinda stuff