For this tool, a digital forensic tool testing image, created by Nick Micus, specifically for testing data carving tools, was used. One of the main reasons for choosing this particular image for this exercise is that Nick Mikus is listed as one of the contributing developers of Foremost. As seen in the first line of Foremost, which displays the version number alongside authors Jesse Kornblum and Kris Kendall. The image can be downloaded freely at http://dftt.sourceforge.net/test11/index.html.
Once you've become familiar with this exercise, you can try extracting data from other images also available on that site at http://dftt.sourceforge.net/.