Here's a collection of ten free transparent frame to add to your photos. These frames were created using the free grayscale masks available on this site, combined with layer styles for Photoshop or Photoshop Elements.
The frames are transparent PNG files at a size of 800 by 600 pixels. The will work in most image editing, illustration, presentation, and page layout software. Simply place your photo as a separate object or layer behind the the frame so it shows through the transparent center portion.
To learn how to create your own frames like this, see my summer splash frame tutorial.