OERTH This map took me several hours, and I was frankly surprised nobody had beaten me to it. I jiggered with the northern coastline of Hyperboria a bit, and added a slew of minor islands. My 'campaign map' for my personal home campaign will probably lack Polaria and Unnamed continent, but that'll appear somewhere else.
Since I have officially given up on ever seeing a Greyhawk Atlas, click on the map for a copy of the .FCW file. Enjoy, and if you come up with any better ones, please send me a copy!