I am still an amateur at landscapes/nature....so that should qualify me to answer. LOL I have several frames that I need to get prints for and I have sold several images that now hang on other people's walls. I'm waiting for a larger portfolio to display more. I have a buddy that owns a coffee shop right down town who said I can hang prints any time I want. I also know a couple other coffee shops I can do the same. Once I get a larger portfolio, and a site set up, I plan to print, frame and display some images to see how it goes. I'm not expecting much, but I should be able to get people to go to the site to see what I have. I shot a house a few months ago where the owner does all her own framing and matting herself. She has the whole set up. I'm hoping to have her help me with the framing and matting for the best presentation possible.
With that said, I know a guy here in my town that makes a very good living shooting landscapes/nature and he does most of his sales via his site. He has images displayed in a few places around town and his business card is there to drive customers to his site. He told me that he hasn't 'needed' to work in over five years. His online sales pay all his bills and then some. Now, he just travels around shooting whatever he wants, whenever he wants. He said it took a few years before he got to the point where the online sales were making him good money. But, he has no overhead from a gallery or anything like that.