I hope someone else can confirm this because I'm not 100% certain, but if I recall...
egdcltd is correct, everything is covered from the 1st and 2nd edition atlases. However, the Atlas Addendum that went along with the 1st edition does have some information that is only available there, specifically the sections on Artifacts, Places of Power, and Lost Technology. I suspect Terry's plan had been to incorporate this material into "Artifacts & Lost Technology" book but that seems off the radar now.