im no expert. but id guess that there is a lot of fetish stuff available for free on the internets, especially the common fetishes.
there is, but if you have a specific taste, and actors are hired to perform who really aren't into it the result is a caricature. the best stuff is produced by essentially-amateurs who will self-produce and throw the stuff up on a clips4sale page, and only 10% of the videos will make it to a direct download / streaming tube site.
I've bought porn approx. twice in my life and both times it's happened about like this.