Download iOS 4.3 Firmware IPSW file for iPhone 4, 3GS, iPad 2, 1, iPod Touch 4G, 3G, and for Apple TV. Stay away from iOS 4.3 update if you need to Jailbreak or unlock your device.
Download iOS 4.3 build 8F190 Firmware from the following links
iOS 4.3 for iPhone 4
iPhone3,1_4.3_8F190_Restore.ipsw
iOS 4.3 for iPhone 3GS
iPhone2,1_4.3_8F190_Restore.ipsw
iOS 4.3 for iPod Touch 4G
iPod4,1_4.3_8F190_Restore.ipsw
iOS 4.3 for iPod Touch 3G
iPod3,1_4.3_8F190_Restore.ipsw
iOS 4.3 for iPad 2 and iPad 1
iPad1,1_4.3_8F190_Restore.ipsw
iOS 4.3 for Apple TV 2G
AppleTV2,1_4.3_8F191m_Restore.ipsw
See also:
Download iOS firmware files (All prev. iOS firmware versions for iPhone 4, 3GS, 3G, 2G)