This is all you need to know about iPhone. From the basic, or each model detail will be covered in this posts. So stick here.
iPhone Manual (PDF)
The iPhone 4 link
Quick Start Guide [PDF]
User Guide for iOS 4.2 and 4.3 [PDF]
Product Information and Safety Guide [PDF]
The iPhone 3GS link
Quick Start Guide [PDF]
Product and Safety Info [PDF]
The iPhone 3G link
Quick Start Guide [PDF]
Product and Safety Info [PDF]