The Springfield Library is a new building released in version 2.3.0 for iOS players on September 21-26 after the release of their new update on September 19th 2012. The building was not initially added to the game until days later, at least not added into the new update. Players are required to download the new “streamed” update to get this building.
By purchasing the Springfield Library you will also get access to a brand new character and he will join your Tapped Out city in The Simpsons: Tapped Out game.
That being said, you need to be at least level 21 to unlock this house, which is quite a challenge for new players.
Requires Level 21, Sanctus Arx Nerdarium
Earns 200 Cash and 20 XP every 16 hours