Order follow-up email campaign

I am trying to create an email follow-up sequence that will go out after a seminar is registered for. The follow-up sequence for each seminar is the same except for Seminar name, date, time and location.

I also need to time the emails based on the date of the seminar.

Contacts may purchase more that one seminar at a time.

The only way I can figure to accomplish is by assigning a tag when a particular Seminar is ordered and than creating Campaign fields for each seminar to merge into the emails along with a custom contact filed to be used in Field Timers within the sequences.

I have over 50 seminars to set-up and want to find a better way.

The seminar information is stored in another database until the purchase is made outside of Infusionsoft. I am looking for a way to automatically populate the emails and the Field Timers with the proper information after a purchase is made.

We are using API to sync with Infusionsoft to create the contact records and apply the purchase tags.

Does anyone have any ideas?