Good photos are ESSENTIAL like GoTo said, but expensive photo-editing equipment isn't. Use good lighting, it'll make all the difference. If you can't get enough artificial light with lamps and spotlights, try taking your products outside and shooting in natural light. Maybe a few objects or props will help to give the product some scale and context. Here's a great article on how to create a professional lighting setup for cheap:
http://www.handmadeology.com/studio-quality-product-photography-with-a-12-set-up/It's likely that you'll take some excellent photos this way, especially if you use a really good camera. Some post-production always helps, though you don't want to over-do it! I use Picasa, so I can definitely personally vouch for its effectiveness. It has all the basic editing tools such as lighting, shadow, saturation, glow, sepia, etc as well as other photoshop-like tools like retouch (which is just like the photoshop stamp tool). Also, Google put in a handy "I'm Feeling Lucky" button to do auto-color/contrast/tone adjustments at the click of a button. If you're looking at hundreds of photos to edit and upload, Picasa can be the perfect tool. I sometimes don't bother opening photoshop because Picasa doesn't slow down my computer as much and does everything I need to make my photo look awesome.
I hope this helps...remember that your photos are the first things your customers see and it's always worth finding new ways to make them clearer and more professional.
Best of luck,
-Ana
