You can use Word's Envelopes and Labels feature to print envelopes. If you want to see custom fields in the Word merge field list, make sure you choose All contact fields under Fields to merge in step 3. Save the merge document if you think you might use it again. After Word displays the merge document, add merge fields, other text and formatting as needed.
The steps are similar in all versions of Outlook, however, the menus are different. You can start the merge from any Outlook contacts folder.
