Where can I download iOS 5.x firmware files for the iPhone 3GS?

Apple is offering the iOS 5 update for existing iPhone 3GS users free of charge. The company will also continue shipping new 8GB iPhone 3GS models with iOS 5 already installed. On your computer, right-click the link below to download the official firmware restore file.

iPhone 3GS firmware version 5.0 can be found here: iPhone2,1_5.0_9A334_Restore.ipsw
iPhone 3GS iOS 5.0.1: iPhone2,1_5.0.1_9A405_Restore.ipsw
iPhone 3GS iOS 5.1.0: iPhone2,1_5.1_9B176_Restore.ipsw
iPhone 3GS iOS 5.1.1: iPhone2,1_5.1.1_9B206_Restore.ipsw