>>1470910You can either put yourself in the place of your target audience and see who is at least mildly popular in each circle, sending a polite message and everything, or looking for a influencer catalog, I know that with Instagram you can use Instajet.
If you choose to go without a catalog, maybe the feature in which you can see where a song is used can help you with the "stalking"? I'm not sure.
The tricky part is making sure that you do not get tricked when paying, try to negotiate. Where I live people who sell stuff normally only pay a fixed % of everything that is sold with the ad link and a little extra. With music it may be harder than this. Depending on where you live you can make an atual contract in paper with those people.
In the future you could plan this better making a plan for a song that still didn't come out, with teasers for the launch date and influencers using it on the day it comes out.
