If an image is on a solid background and does not have any shadows, the background can usually be removed, leaving the image on a transparent background. Below is a basic tutorial on how to remove the background and create a .png image.
First, open the image in Photoshop. Be sure the layer palette is active (hit F7 key) (Image 1). Since the original layer is locked, it must be duplicated by dragging the locked image to the icon with the turned edge. Once duplicated (Image 2), drag the original, locked layer to the trash icon, which leaves an editable copy of the image
Select the "magic wand" tool from the tool palette and click on the white area of the image. You will see the "marching ants" around all the solid areas of the image. (Image 4) Click the delete key from your computer keyboard, and the white (or other solid color) will be removed and you will be left with a gray checkered background, which indicates that area which is transparent. (Image 5) The element can now be moved freely and added to your work or document or you can now add another background color or design layer under the element. (Image 6) Finally, save the image in a .png format to preserve the transparency of the image.
When completed, choose "merge visible" from the layer tab to retain the transparent background and save in the .png format, or flatten the image to merge the layers and save as a jpeg. Once merged, the element is no longer on a transparent background.