Yes, its automatic; I do mine in the callback page.
Remember I gave you an edited version of my callback page, some of the the bits I edited out were the email bits. Basically it goes:
If the callback password is correct and the transaction was successful...
Update my database with the stuff I want at the appropriate orderID
Send out an email along the lines of:
We are emailing to confirm we have received payment for your order (orderID).
Here is a summary of what you purchased:
Now drop in a pretty looking table, with a repeat region, that shows items matching the orderID (from the ordersdetail table in the database)
Job done, fully automated.