To access the Western Territory Address Book in Outlook do the following:
Click Address Book under the Find section.
The address book will open.
You can select a different address book by clicking the drop down arrow next to the address book.
Note: Offline US West Address Book is the default address book.
Search is by name, first and last. You have the option to perform an advanced search by clicking Advanced Find.
Then you can select to search by last name or any other field.