I have previously looked for the following; however, I have only found how to implement it. I am wondering if someone has developed a mod/plugin to add messages to the email that is sent out when a purchase has been made to include additional information about the item or combination of items.

I currently have been modifying the applicable order or orders file to add information subject to the order placed; however, am willing to develop something if it doesn't exist to handle additional messages. An example is: an event that normally requires say a pair of people that can be sold in single sets. When purchased as half of a pair, the sent email includes a message to indicate that we are still purchase from a second individual that they have named. Or more particular, an online purchase for an event let's them know that the item is available at the box office of the event.

Let me know, I hope to offer what I can if it doesn't exist yet.