Worked up a multi-level core data schema last night for storing and handling data, and wrote a loader to allow importing files into the data store, allowing me to provide default data without hard-coding it into the app itself.
Core Data is an interesting technology. It has some weaknesses compared to SQL databases – there are no “uniqueness” tests built in, and everything is in memory for large data sets which is a bigger issue on memory-limited devices like the iPhone – but it also provides an excellent wrapper for managing data without having to write a lot of code yourself.
There are actually a number of decent tutorials, including Apple’s own documentation, but it’s not a “beginner” topic, and I’ve found that the only way I could get my own head wrapped around it was to actually work with it, so there won’t be tutorials coming soon.