A map of all of the U.S. congressional districts (as of the 110th Congress).  To find the district's number, look at the district, compare with the color code at the bottom to get number.
Based off of: [1] for most boundaries, [2] for Georgia, and [3] for Texas.
Mr. Matté (if there is an issue with this image, contact me using this image's Commons talk page, my Commons user talk page, or my English Wikipedia user talk page; I'll know about it a lot faster)