Hardcopies or digital?
Dungeon Magazine had a 4-map set that might be a little better, since it's four quadrants, but I don't think the details are to the level you are looking for.
There are some available on eBay:
** expired/removed eBay auction **From the Ashes might contains some additional regional map details, post–Greyhawk Wars. I haven't checked to see if any of them would be helpful, though.
If you are willing to work with digital files, my go-to source is here:
Atlas of the Flanaess 576CY - Anna B. MeyerI use the single-map version. It's a massive file, but if you've got the hardware to handle it, it's a great map. The individual pages are awesome, too, and easier to work with.
There's quite a bit of Living Greyhawk digital content that might be helpful, as well. There's at least one specific map of the Kingdom Of Keoland.