The library shelves are full of books on self-sufficiency and smallholding, living the good life etc etc, but most of them are probably not written by people who have actually done it themselves... Full of errors and misguided statements....
Really the best is still.... For realists and dreamers... John Seymour and after that, get specific books on what exactly you are doing. I found the "starting with... " series really helpful and of course Tim Tyne on sheep, Mackenzie on goats (written last edition in early 1990s - still not out of date!), Carol Harris on Pigs. I have several really good goat boooks from the 1970s and 80s, and other than up to date veterinary books I don't need any new and don't buy any anymore...
I am not sure that the effort to write another book on smallholding is quite justified, but that is my personal opinion, so please no shooting down and disregard if it is not helpfulfor you.