We are using FM Server Advanced, and data gets inserted into our database via the internet. For example our online store stuffs customer and order data from their system into our database. Works great.

Later I go in and "sync" up the customer information so that users who checked the "contact me with update information" get subscribed to our mailing list database.

I would like it if this sync happened automatically when a record was created in the server. How can I create a script that runs automatically on the server side when a record is created?

The easiest way to do this would be to force users to create records using a script you created, rather than built-in commands. Then a subscript which adds them to the mailing list can be run conditionally based on whether a box is checked.

I think there are some script-triggering plugins that will work when triggered over the web. You might check out Events or Activator or MMScript to see if they work the same way for web as they do for FMP.

This all happens sans user, actually. some server somewhere on the web pushes data at our server in the form of...

http://IPADDRESS/fmi/xml/fmresultset.xml?-DATABASE&-lay=LAYOUT&OrderInfo=BLAHBLAHBLAH&-new

That creates a record in the database and I'm happy. However now I need to sync it up with our address book database. I'll look into the third-party stuff you mentioned, I guess I should assume that FileMaker Server Advanced can not (by itself) automatically run a script as records are created?