See, I don't have a whole lot of knowledge of the setting, so I as yet don't know where I would set it. I will certainly make it a point to look for the Xa-ar area.
I have Emer Atlas 1 and 2, each with a date of 2002, so I'm guessing I am fairly up to date in that regards. I also found a couple of adventure books, but they specifically reference Rolemaster and Fantasy Hero, and are from 1989. So those are definitely the oldest of the books.
Thank you, all. I will say that since picking these up, I have started reading and wonder why I passed them up all those times I could have gotten them years ago...
It seems to have many of the elements I've been shoehorning into my d20 game.