Zazzle | Custom T-Shirts, Personalized Gifts, Posters, Art, and more is free, other than they'll take a fee on every item you sell, but that cost is known by you up front per type and size of the item, and you can set your prices there accordingly to cover that cost. They'll then take care of the printing, shipping, billing, returns, etc., and paypal you with your profits.
You can put your images on prints or posters up to 6 feet wide or tall, plus a wide variety of accessories like mugs, t-shirts, hats, calendars, magnets, key chains, skateboards, iphone cases, and lots of other stuff. Customers can choose sizes, paper quality including canvas, frames, matting, etc. However, you don't make any profit on matting or framing, so that's kind of a bummer - but then, you don't put anything into that aspect of it either, so...
You can choose from many different storefront layouts, or cobble one together on your own if you know a bit of HTML or CSS, and you can set up a different store front for each project if you like, but they're still all managed by you from one user name and account. Then you can send a link to the store(s) or particular images to whomever you like, or post them to the world on FB or make business cards with it on them, etc., to fire up your advertising and networking.