I've heard that for small niches, Facebook ads work pretty well. An acquaintance of mine used this for reaching some pretty specific niche, like males from a s

I've heard that for small niches, Facebook ads work pretty well. An acquaintance of mine used this for reaching some pretty specific niche, like males from a specific country, in a specific age range who like some type of cars. He said that it worked better than other online alternatives, but as always YMMV.