Phil on photographing jewellery:
There are really two ways to go: show the jewellery on its own against a fairly neutral background, a silk cushion or in a light tent, or show the jewellery being worn by a model. The first method is great for showing detail in your craftsmanship: the second is better for creating a mood and helping your customers grasp the magic. By magic I mean what the piece gives to you as the buyer beyond the physical, be that elegance, sophistication, a cute quirky appearance or a bad ass look. It's why jeans manufacturers don't all just have pictures of a pair of jeans against a plain background :) The second method is more expensive, more complicated and more fun.
Reflections
Sometimes you'll want reflections - to make gems shine, for example. If you need to control reflections, use something to diffuse the light: a light tent will do this for you, or if you're using a single light source hold a diffuser (£5 from ebay) in front of it. At a push, a plastic shower curtain can work.
Sharpening
If your work features lots of intricate detailing - carving, cogs (like Bernard's Witch's Heart) or small gems, sharpening in post-production can really make it 'pop'. Photoshop will let you sharpen only the parts you want to - the jewellery - and not the parts you don't, such as the model's skin.
Colour Casts
Make sure you white balance correctly: you want the colours in the final image to truly reflect the item or you'll have unhappy customers. This is easy in a studio but needs a little more care if you're shooting at home with a table lamp.
You can contact me here. I do take commissions if you'd like your jewellery - or other Etsy work - photographed but I'm also happy to answer questions if you have any.