This:
https://www.amazon.com/World-Robert-Jordans-Wheel-Time/dp/1250846404
Older fans will call it "The Big White Book" because the original printing had a white cover.
It's full of interesting things. You shouldn't read it until you've finished book seven if you're worried about spoilers.
I am thinking of this 1997 guide book and other "official" artwork from before he passed.
Great work. I highly recommend that you consult Jordan’s approved atlas from this book: Limited-time deal: The World of Robert Jordan's The Wheel of Time https://www.amazon.com/dp/1250846404/ref=cm_sw_r_cp_api_glt_fabc_dl_Z2CXG7E803D4G05B6RE0
The World of Robert Jordan's The Wheel of Time https://www.amazon.com/dp/1250846404/ref=cm_sw_r_apan_glt_fabc_WBXX1ARB1WEA9W8N9RHN?_encoding=UTF8&psc=1