Out-of-the-Box Lawyering has some tips and tricks for using Google to find photographs and drawings for use in cases:
Do you need a diagram of a heart? Go into Google and just enter Heart. But, before you click on Search, look above the Google search bar and click on "Images." Then click on "Google Search."
If you want to limit your search to JPG files, or to GIF files, or to PNG files, you can do that also. Just click on "Advanced Image Search" at the top of the main Google search page. Then, look down the Advanced page and you will see filetypes. You can then select the type of file you want to see and to download.
For other hints, read the full post.