The best example I can find is the Netflix slidedeck. I am not speaking of the content (which is good), rather about the way it was created. The author discussed the company culture with people in the organization, interpreted what they said, and she was the sole author and creator of the document. In my experience, this is the best way to create such a document.
I have been through many meetings at many companies where we attempted to creat a manual by committee. The results was always the same. Every person in a group of people will have a bee in their bonnet about something different. The group discussion will bounce around endlessly, and the opinions will never crystallize onto a unified view on any topic. A document produced this way will be a hodge-podge, or it will be so washed out that it has zero impact.
You need to listen to everyone's opinions on the matter, then distill them into a few general principles. Each person will present problems from their past that they want to prevent. They will blame the problems on the culture, and suggest changes to the culture to solve the problem. However, some part of the problem is undoubtedly due to their personality. Your job as listener is to remove some of the personality portion of the problem and extract the true cultural aspects. Universal personality traits (ego, ambition, introvert vs extrovert) have to be factored into your solution, but you may not want to cater to idiosyncrasies.