There are so many freely available books in Theravada that the problem is deciding on which I should be reading first
Ha, yeah... and even once you finish some there still so many more to go!...
It's good, isn't it?
"Do not force others, including children, by any means whatsoever, to adopt your views, whether by authority, threat, money, propaganda, or even education." - Ven. Thich Nhat Hanh
"Whether I were to preach in brief, Sāriputta, or whether I were to preach in detail, Sāriputta, or whether I were to preach both in brief or in detail, Sāriputta, rare are those who understand." (A I 333, Sāriputtasutta)