The Palm device's main apps allow you to record events, addresses, tasks and misc. notes.  With the exception of the Date Book's events, which has a filing and ordering mechanism based upon date, the other apps will, after a while, begin to resemble that classic haystack, where it is impossible to find that pin.  And while the Find function will find one or more occurrence of an item you want to see, it will not group like items together.  Thus, if you have a few hundred entries in your Address Book, and you want to throw a party for friends and business associates, it will be a chore to get them all together, going through them all one at a time.  Similarly with the Memo Pad, even 50 Notes can be a haystack.  The way you keep organized within this world of easy to add and harder-to-keep-organized addresses, tasks and notes is to assign your entries Categories.  Yes, Categories.

Again let me explain through illustration:

For my Address Book, I created the following Categories:

For my To Do List, I created the following Categories:

For my Memo Pad, I created the following Categories:

As you can see, different types of data deserve different kinds of Categories: the Categories for the Address Book reflect the nature of the relationship or connection (family, friends, work); the Categories for the To Do List reflect where and how the task will be performed (thus, I group tasks that are phone calls, indoors chores, out-of-doors chores, work-related); Memo Pad Categories are less well-defined, they reflect the shape of the note (List, Note, Outline) or the context of the note (Financial, Personal, Work).

Don't take these Categories as gospel, they are what I came up with, and my Categories are still in flux.  Use them as inspiration for your own Categories, ways to keep YOUR data organized.

By the way, even your apps have Categories; Palm knew you would use your device for more than keeping your life organized.  My Applications' Categories are:

By the way, if you're wondering how I got Tetris, Dictionary, Dilbert, Zagats, etc. onto my "Electronic Organizer", perhaps you should go right to my Downloading Third-Party Apps Tip.