Most of the places that let you upload and sell prints are a subscription service (like SmugMug and SnapFish etc).
There is a company called
PhotoReflect who offer a free service which allows people to order prints and you can password protect certain groups of photos. Prices are in US$ and I don't know what they are like to use as I've never used them. They charge a commission of 15% on every sale and then a 3% credit card handling fee which comes out of your sale price.
You can also sell through
devaintART. It's free to join and have a membership but I don't know what the charges are for selling (assuming that there are some!).