There are two sets of documentation to get you started:

Installation & Tutorial will provide you with a quick start guide to getting IIP running with Mozilla's ChatZilla IRC client, as well as basic commands for both IRC and Trent, IIP's identity and channel management 'bot.

Official Documentation is just that - the official IIP documentation which contains in-depth sections on installing IIP, IIP architecture, Trent, and much more.

Wiki, a collaboratively-edited website which allows all users to edit any page or even add their own.