Here are the links to firmwares:

iPhone 2G (EDGE): 1.00, 1.01, 1.02, 1.1.1, 1.1.2, 1.1.3, 1.1.4, 2.0, 2.0.1, 2.0.2, 2.1, 2.2, 2.2.1, 3.0, 3.0.1, 3.1, 3.1.2, 3.1.3

iPhone 3G: 2.0, 2.0.1, 2.0.2, 2.1, 2.2, 2.2.1, 3.0, 3.0.1, 3.1, 3.1.2, 3.1.3, 4.0, 4.0.1, 4.0.2, 4.1

iPhone 3GS: 3.0, 3.0.1, 3.1, 3.1.2, 3.1.3, 4.0, 4.0.1, 4.0.2, 4.1

iPhone 4: 4.0, 4.0.1, 4.0.2, 4.1

iPod Touch: 1.1.4, 1.1.5, 2.1, 2.2, 2.2.1, 3.0, 3.1.1, 3.1.2, 3.1.3

iPod Touch 2G: 2.1.1, 2.2, 2.2.1, 3.0, 3.1.1, 3.1.2, 3.1.3, 4.0, 4.0.2, 4.1

iPod Touch 3G: 3.1.1, 3.1.2, 3.1.3, 4.0, 4.0.2, 4.1

iPod Touch 4G: 4.1

iPad: 3.2, 3.2.1, 3.2.2

Bootloader Images: zip with 3.9 and 4.6: download here.

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