Particularly ones set before/during/shortly after the prequel trilogy? I have a pretty good idea of where to go for the New Republic stuff.
I don’t read much in that timeframe but…
- The recently released Kenobi, set immediately post-ROTS was excellent.
- I read Rogue Planet years ago and remember liking it well enough though I don’t recall much else. It’s set a few years post-TPM, early in Anakin’s apprenticeship.
- I’ve never read Shatterpoint because it’s a Mace Windu book and I don’t care for him, but most people who have say it’s excellent.
- If you haven’t read the novelizations of the prequel trilogy, particularly the Revenge of the Sith novelization, drop everything and do that.
- The only other things I think I’ve read in this time period are the YA Jedi Apprentice (which follows Obi-Wan early in his apprenticeship to Qui-Gon) and Last of the Jedi (which follows survivors of Order 66) but idk if you want to read YA.
Anyone else?
Immediate? Kenobi. Very good.
To understand the Sith and their thinking – Darth Plagueis
Best before A New Hope – Karen Traviss Commando Series
Comics about Moff Trachta.
Imperial era – reference books on Guide to Star Wars Characters
Death Star
There are more on Wookieepedia