How to enable print option in iPhone apps
Printing in iOS is only available in iOS 4.2. Since 4.2 is still under NDA, any discussion of printing facilities in 4.2 would be a violation of NDA.
The one place where you can discuss 4.2 without violating the NDA is on Apple’s Developer Forums. If you have an Apple Developer account, you can find the forum here (ADC login required): Developer Forums: iOS 4.2 beta.