Last year I wrote an little e-book for MS Learning that shipped on the CD for a bunch of Office 2003 titles. They've now put that e-book on the net for free. Here's the link and a blurb.
Insider's Guide to Microsoft Office OneNote 2003If you run the installer, you'll find the CHM file for the book in the folder C:\Microsoft Press\Insider's Guide to OneNote eBook.
OneNote is a product whose time has come. It's designed to make it easy for users to take notes and to organize personal information and thoughts. The first thing that a lot of people say when they see OneNote in action is, "I've been waiting for a program that does stuff like this all of my life." The second thing they say is, "What took you so long?"
Keep in mind that this book was written for version 1 of the product. The SP1 (beta) version of OneNote, available here, is absolutely fantastic and it even offers an API that will let you program to it. Omar Shahine has one of the best Weblogs around for OneNote information.