FotoFuze lets you make professional product photography out of ordinary photographs from ordinary cameras. For free.
To use the photo enhancement service for your product photography you need to sign up first. You don't necessarily need an Etsy account, but if you do there are some Etsy-specific features such as easy uploading to your listing and by keeping your photos public (there is a privacy setting too) you could even get additional sales, as there's a buy button beneath public photos that take visitors directly to its product page.
Need an example? Here you go ... and in case you love this stunning necklace you can buy it here.