If it's your
market, you should already have a pretty good idea of who the influencers are.
(And with luck, you're one of them.
Who writes the industry blogs you read most frequently? Who do you see most often quoted in other industry blogs or in industry publications? Who in the industry keeps showing up over and over as "you might also know" on LinkedIn? Who shows up over and over again as a speaker at industry-related conferences?
These would be the ones you'd look for first as "influencers." If you really want to make sure you've caught everybody, find out who these influencers themselves listen to.