EDIT: I think I'm close to solving this now. i will self-answer if so
I've been stuck on this for a while now - I want to use the sample Oracle Human Resources database. I've been studying through these instructions to no avail.
So I have downloaded both Oracle Database 11g Express Edition, along with SQL Developer. And I can play with it and create a sample database. But I don't know how to use the HR database.
any tips appreciated. thanks