Etsy's a great online small business tool, and I've actually run a little shop there the last two winters for crocheted items. There are also a ton of photographers who have set up shop, and every now and again I like to peruse them.
I've thought about selling photos on Etsy, and if I ever do you can expect a tons of posts about that process. In the meantime I just like to see what the others are doing. There's a general model that most seem to follow in terms of photo production, pricing, shipping, and things of that nature, so it's good to know. You never want to be the one person standing out for all the wrong reasons.
For reference, here are a few (out of the MANY) Etsy photography shops that I like for one reason or another.
Lisa Caeser Photography. I like the many different subjects she uses.
Slight Clutter Photography. She (or he) keeps the photos colorful, and sometimes whimsical, and though there can be too much of the smoky/hazy/fairy tale-ish stuff on Etsy nowadays, I think she/he has struck a good balance.
SKnight's Art Photography. Great photos, but also, check out the greeting card. That is exactly what I am gearing up to do within the next month. I can't wait! I plan to sell them in stores (boutiques and the like), but if I do get an Etsy shop for prints, why not slap those suckers up there too?