A) DVD rentals or purchases. B) Tube sites like Pornhub or Manhub. C) Pay sites like Bangbros, Brazzers, or Oldergaydaddies. D) Free downloads from torrents or file sharing sites. E) Pay per view or premium pay channels F) Other(explain).
For me it's D. Generally I know which pornstars I like and when they have new stuff get it.

I usually just Google a particular subject - i.e. I'll Google "big black tits" and then just watch the clips - I particularly like when the Google search gives me a page which contains many videos on just that topic (e.g. "big black tits"; etc)