Or, if it's the simplest resource on it out there, are there any prerequisites for learning it/ skills/ knowledge that would help?

I'm trying to build up a basis of skills so I can participate better here, but I've got a long way to go. Most of my skills in science, maths and logic are pretty basic.

Definitely read Gödel, Escher, Bach. Aside from that, here's a great list of reading and resources for better understanding various topics discussed on LW. (The things under Mathematics -> Logic and Mathematics -> Foundations would be the most relevant to Löb's Theorem.)