Printing from an iOS device? Easy if you have an AirPrint compatible printer. See lists of H-P, Canon, Epson, Brother and Lexmark
at this Apple Support site:

IOS-Productivity Pre/Post Test

Help on Keynote

How to Play PowerPoint Presentations on iPad

Adding video to Keynote

Help on Pages

Help on Numbers

Setting up iCloud on a Windows Computer

User Manual for Good Reader

Review of Penultimate on TUAW:

How to get a guide for iOS iWork in the iPad's iBook Library: