I have a Canon Rebel with the lens kit it came with. Can't afford anything else and I've had it for years. For backgrounds, I use whatever I have around - most of my modeled pics are taken with the white wall of my patio as the bg:
http://www.etsy.com/listing/114355247/extra-soft-forest-green-fingerlessand I often use a sheet of white cardstock as the background for small things:
http://www.etsy.com/listing/124035440/mens-black-beaded-leather-wrap-braceletI'm also really fond of taking photographs of jewelry for my blog on the steel blue cover of a notebook I got from manipulatedpaper.etsy.com, or straight up on my desk. You can see more of my work on lixhewettphoto.wordpress.com and aclassicnotion.wordpress.com
To me, the camera does make a huge difference, especially in terms of how easy the photos are to edit into shape afterwards. I love and swear by my Canon. But I do okay without any other equipment. It may make things easier for you, though, and if you can afford it, I say go for it. I'd probably have a lot more things if I could buy them - at least a tripod, a remote, a lens that didn't get stuck and a better lens for full body shots. But I make do with my lovely camera and natural sunlight. My room gets really good light from midday to 5 pm or so. Excellent to shoot small items. And my patio's okay in the morning and the late afternoon for modeled shots.