If anyone has feedback on this topic, there are probably many of us hackers that would sure appreciate some insight.
2) Read about marketing people with technical skills to understand what they do. Decent but dated example: http://okdork.com/2010/10/14/how-mint-beat-wesabe/ Many other examples blur lines too (patio11, SEOMoz, etc)
3) Couldn't tell if they had investors but that might be a source too. As hackers can find hackers, I bet investors can find marketers.
4) Find a successful competitor who filled the position. Write a job description based on that person's bio.
5) Consider trying out a contractor or consultant first. If having that person in the office would destroy culture, maybe you don't need them.