If you're able to determine which session it is, I can ask the presenter of that session. I've spoken with the Adobe Launch product evangelist that presented in most of the Launch sessions and he indicated he wasn't aware of any Excel workbook for Launch. I also don't know how an old excel workbook would work with Adobe Launch since Launch is brand new.
In one of the developer sessions, a web app was shown that used the APIs to create properties, data elements, rules, ect. This wasn't something that was going to be shared though. It was a simple example of how the APIs could eventually be used to create a "standard" implementation for your company.
Sometime after the release of Launch, the APIs will become available to customers & partners to interact with using your own apps. At this point, there isn't anything officially built for Excel.