In recent versions of FileMaker (10,11,12) you can set up FileMaker to send e-mail directly using SMTP. For this you need an account that will accept the SMTP message. If this is an internal e-mail server you can work with your System admin to make sure that SMTP is enabled for the account you want to use. You can also use Google's gmail by setting up an account for this purpose and storing the user account and password in the database. All of this can be scripted. Check out the script step, Send Mail. You can hard code values, use fields or variables for the values required to send the e-mail including the body. This will let you include the doc #.