Ah, Reddit - my favorite site when it comes to the Internet, and pretty much the best destination if you want non-commercial access to porn. The subreddit 'amateur' is of particular viewing quality, because people submit and share pictures of girls that aren't professionals and are getting nude and rude for their love of X-rated entertainment.
/r/Amateur currently has 193,000 subscribers with new daily posts showing you the cream of the crop when it comes to young, nubile ladies that define the amateur niche to a tee. Rest assured that no images here fall into the category of fake or produced material trying to look amateur - it's the real deal, and because it's on Reddit, you know there's not going to be any messing around.
I suggest if you want to get a feel of the material, just sort the content by highest rated of all time. That'll showcase just what type of amateur material this place has to offer.