I have a list of contacts in my own database that I am accessing with a VB
program that I have written. I want to loop through this list and export them
to my Outlook 2007 contacts folder.

I am starting with the following code to access my Outlook folder:

Dim Contact As Outlook.ContactItem
Dim ContactList As Object
Dim ContactsFolder As Object
Dim OutlookApp As Object
Dim OutlookNamespace As Object

Set OutlookApp = GetObject(, "Outlook.Application")
Set OutlookNamespace = OutlookApp.GetNamespace("MAPI")
Set ContactsFolder = OutlookNamespace.GetDefaultFolder(olFolderContacts )
Set ContactList = ContactsFolder.Items

I need to find whether a contact is already in the ContactList based on the
CompanyName field. If it exists, I want to update certain fields in the
ContactItem. If it doesn't, I want to define a new ContactItem.

I have used collections very little, and so I'm not sure how to efficiently
find an item in the collection and know whether or not it exists. Thanks for
your help!