I'm looking for any kind of history books about WWI, either in general or focusing on particular events/sides of the war. There's just so much available that I don't really know where to start
The Guns of August by Tuchman and The Sleepwalkers by Clark are both classics at this point (especially the former). I also liked Europe's Last Summer by Fromkin. All three are about the outbreak of the war though. But from there you will have a good basis to start exploring more particular issues or fronts or whatever.