Well not sure if this is what you're looking for. But this could work too, at least it did for me.
Well as the story goes there was a client that wanted the app to start with a given set of data. Usage of CoreData was not a requirement though, but I wanted to learn it out of desperation(as it had already cost me a couple of jobs).
So here's what I did. I loaded up the SQLite with the data that client wanted and on first launch of the app I simply accessed those values from SQLite DB and updated my CoreData with it. From then onward I just referred to the CoreData.
A hack or even an unnecessary added step, i know, but it did get the job done.
Though at the end of it I would just say use an SQLite DB if you want pre-populated data.
Hope it helps. Feel free to ask if you have further questions.