Try white tissue paper. Everyone's got some of that in their closet!
Or if you want to get really DIY fancy, make a lightbox from a cardboard box:
Strobist: How To: DIY $10 Macro Photo Studio
I use two pieces of white foam core board (arranged in an "L" shape) and a gooseneck desk lamp.
This is exactly what I've used for most of my best shots! I used white tissue gift paper for the sides, and I left the bottom of the box and just taped my backgrounds to it using painters tape so it is easily removable.
Here's a pic of a setup I've used in the past:
Definitely NO FLASH. I use 3 different desk lamps for each angle.
Here she is up close and this was taken in the evening with no flash.
I also set my camera to the FOOD setting (or whatever the setting is for still life). Also, make sure to set your WHITE BALANCE on your camera. It made a huge difference for me. I couldn't figure out why my pics always had a yellow hue to them.
I didn't used to have a tripod so I just used a steady box or even a tuna can that was the right height so I didn't have to hold the camera. Here's one example of a medicine box tripod... lol... and how I just added a white background. Make sure to curve it at the back to make it seamless.
I have also used just a white plastic bin on it's side in outside natural light and it has come out pretty good.
Another tip (if you don't have Photoshop or similar products) is to use Photobucket to adjust the brightness/contrast of your picture.
Here is an example of a pic that I just used the Auto Fix feature in Photobucket.
Before and After
Hope this helps and that you post pics!