I think it is time to put down the pen on this one. Thank you all for your patience over the past year+ that I have been head-down buried in work on this. Greyhawk and Blackmoor began their journey together and bringing them back in harmony, while a daunting task, has been a true pleasure.
Here is the promised Greyhawk guide to Blackmoor.
It is a dropbox link so hopefully will work for you all, but if not I will be posting it elsewhere in the coming days.
In a nutshell, this book serves as a guide to people, locations, history, and geography of Blackmoor for Greyhawk players, including a deeply researched timeline. It brings Arneson's traditional Blackmoor back to the Flanaess where it started.
UPDATE
For those (like me) who enjoy having real books, I've created some print-on-demand friendly files. This includes a cover you can upload to a service like Lulu, if you like, and have your own premium color copy printed as a book.
The most up-to-date version is 2c.
Enjoy.