I wonder also if there might be a Facebook group that would suit you. I run a really small-time genealogy/family history blog and after joining Geneabloggers at Facebook I'm now in regular contact with over 400 blogs that in turn connect out to other blogs. There must be something there for you.
The other thing I do which works for my history niche is to take part in Blog Carnivals.
Since no one has mentioned this I'm thinking it's kind of an "uncool-not-for-film-students-type-of-thing" but in case you're interested here's the place where they list a lot of them. I immediately saw one for film production.
Evelyn in Montreal