I hated the way Treo displayed the contact by last name and first name. I also did not like they way Treo would take the main contact info from my Outlook.

So, this is what I did.

I created Treo folder under personal folder in my Outlook:
Outlook
Contact
New Contact
and created “Treo” folder

I moved the Treo folder to "Personal Folder".

Click on HotSync
Custom
Scroll down to "Contact (Outlook)" highlight it and click “Change”
Settings
Browse
Personal folder and highlight Treo

Now you can copy all your main contact into Treo and make all the changes you wish.
I typed full name in the last name section.

This way, I only have the contacts I want in my phone and keep all the main contact on my Outlook.

Hope this info was useful.