I'm watching a doc on BBC4 right now called For All Man Kind about the 24 men who landed on the mood. It's very interesting. Check it out on the iPlayer if you can.
It's easier, safer and much, much cheaper to study the moon and the rest of the universe without putting a man on it. That's why no one has been back.
I think you mean Moon not mood. ;-) and it was 12 men who landed on the moon. Two each from Apollo 11, 12, 14, 15, 16 & 17.