Fox Sparrows in our area are a beautiful dark, rusty color. Arriving in the fall, they are continually scratching the ground with their large feet looking for seeds and bugs. Although considered a ground feeder, they fly up to our hanging seed feeders and peanut butter feeders.
A beginning birder can often confuse the Fox Sparrow with a Song Sparrow. You can also see these two birds side-by-side in Who's Who. (You might have to scroll down the page to find them.) Also, the Fox Sparrow can also be confused with various thrushes. See the Swainson's Thrush for an example.
The above image is a partial-albino Fox Sparrow. He has a ring of white feathers. Check out the Royal Society for the Protection of Birds for more information on albinism and other interesting information on abnormal feather coloring.