I got caught up in the publishing vice and often tapped into the graduate student pool when I was looking for writers with the research chops to delve into one

I got caught up in the publishing vice and often tapped into the graduate student pool when I was looking for writers with the research chops to delve into one of my juicier subjects. One of the most effective tools I discovered was to get professors I am friends with to introduce me to professors in the field that I was looking to cover. Once I had my 'in', those professors were always extremely open to introducing me to graduate students they personally know, or more generically, introducing me to Graduate Students' Associations (every University I know of has one, or something similar). If I didn't know any professors, I would likely go directly to Graduate Student Associations, though be prepared - higher education can feel rather closed off, so they may view you with suspicion until you get your in!