Kinda depends on the type of reports you're trying to create and how you want to share them. Rather than sit and watch something, I'd still encourage you to just create test bases and see how things work in action. Press buttons! That said, for jumping off points and inferring from your other thread, you're wanting to sort registrations into various buckets...
If the reports are just for organizing information in various ways to help you or a small team make sense of it, using filters and views are super easy. Create new views (I always like to leave a master data view that doesn't get filtered) in your base, and then apply filters to them however you need. You can then print those grid views like a spreadsheet out if necessary (click on the down arrow next to the view name for printing).
If you're making reports that need to look snazzy with graphs, then use Interfaces. Start with a basic Dashboard interface and play with it from there.
If you're trying to print individual records out to physically hand to/assign to people, then your looking at either the Page Designer extension or setting up another Interface view.
I'll say that turning the digital data into physical printed materials is one area that I don't love how AT handles things. It's doable but it takes a lot of formatting work, plugging in additional tools, and finding workarounds.
