I'm a programmer in my 30s but never really sat down and grasped proper spreadsheet/XLS skills. I want to use libre office calc offline for personal finances and related stuff. Out of the myriad resources, what course/book would you recommend in this context for an XLS dummy?

Just google as you go? We are programmers, so we are very used to learning things on the fly. 😄

Tip: as a programmer, when dealing with excel you'll quickly find yourself chained because of the freedom programming languages in general have compared to something like excel Avoid the urge to switch to programming language, lookup the docs and work with it, just like you'd do when learning any new piece of tech