Hubby bought a PS3

My husband decided to buy himself a PS3 and now he is always playing games on it. The games are very costly though. He bought Skyrim for $50 and Fallout for $40 from GameStop. He'd like to buy more games to play but currently between our five year old Fox Terrier dog Arriana, our seven month old son Chase, bills, and groceries we just cannot afford it. I've been checking online websites for cheap PS3 games but I believe the system is too new for popular games to be offered for less than $40.