This lesson already assumes you have an address book.
Click Start.
Place your mouse over All Programs.
Click Microsoft Word.
Click >Tools >Letters and Mailings
>Envelopes. 
Click on the Envolopes tab at the top of the window.
Type in the return address.
Click Add to Documents.
Now we need a toolbar named Mail Merge.
Click >View >Toolbar >Mail Merge.
Click the Open Data Source button.
Click My Documents that is on the left side of the screen.
Double click the name of your address book. (You could also click your file once and then click open).
Click OK on the next screen that talks about sheets.
You have to get your blinking cursor where the sending address is going to be.
Click were the sending address should be.
If you get a long black line click on it. You have to get a blinking cursor where the sending address should be.
Click Insert Address Block.
Click Ok on the next screen.
Click View Merged Data to see how it turned out.
Click the left and right arrow to inspect your envelopes.
When you are ready click "merge to printer."
