When you installed the software that came with it, there should be something like "Palm Desktop" that gets installed on the PC. One of the categories is "Address". You can use that as your database, I think.
(All of the information on the Palm is stored in various databases, I think.)
You can create your own categories on the Zire. You don't delete icons, you just make a new category with the applications that interest you then just display that category of interest.
You probably need to read through the Handbook:
[link|http://www.palmone.com/us/support/handbooks/zire_ug.pdf|http://www.palmone.c...books/zire_ug.pdf] (but you probably have it already).
HTH.
Cheers,
Scott.