I would like to do this myself. So searched and found an answer at a blogs.office.com site - http://tinyurl.com/6685726

It is a fairly detailedwriteup. The summary is:

The basic steps to creating a mail merged e-mail from Outlook are:

1. Select your contacts in Outlook
2. Select to send an e-mail in the Mail Merge dialog and choose your subject
3. Compose your e-mail in Word – inserting fields where appropriate
4. Preview and Send

I am going to try it. I am sure it will work.