Hey Ian,
I'm returning myself after a few years of being away, it's pretty painless to get up and running. There are tons of resources to get you started.
I would recommend downloading the server package and following the directions. Be patient and take your time with the readme's. If you run into trouble ask specific questions. I couldn't tell you what issues you'll run into so be specific, it helps anyone that wants to help you give you direct advice.
To play, at least for me, I am using UOSteam. It seemed like the simplest to set up. That's for the classic client. For the Enhanced Client theres a different set of things to do.
Good Luck!