My favorite genres of books at the moment are dystopian and apocalyptic/post-apocalyptic. My greatest source of book referrals is from a Facebook group called Band of Dystopian Authors and Fans (BOD). It’s a public group and they are a lot of fun. https://www.facebook.com/groups/bandofdystopian/
They fully support authors & encourage them to promote their books, but it is largely a discussion group. Authors can promote their books once a week. The most fun though are the launch/release parties. There are games and prizes and good old fashion fun!
I’ve met so many authors through this group and have gained a wealth of knowledge from them. It’s fun to help them out by being a beta reader or advance copy reviewer. So many of them are indie authors and have such wonderful talent.
Another great group that I follow is Committed Authors and Readers Only. It is a relatively new group and is rapidly growing. https://www.facebook.com/groups/897626200306462/ Author Ian Smith started this group to have authors and readers support one another. Unlike BOD which has a specific genre it caterers to, CARO includes every area.
I also belong to reading challenge groups. Whatever you like to read I’m certain there is a discussion group out there for you.