You can have free online portfolio websites, such as DeviantArt or Shadow or Behanced. They give you your own page where you can post your photos and even sell them, each sale you get a percentage.
If you have the money, you can buy a domain (yearly fee) and a host (monthly fee) and do it that way. But then you would have to find a printer and work with them to sell prints. Then you have to deal with shipping as well. So it's a bit of work.