Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada
In the format of a printed guide; published by the Nebraska Extension Service out of the University of Nebraska.

Has identification keys, photographs of pinned specimens, and distribution maps for most species in the state. It is a good reference for identifying Grasshoppers, useful in much of the northern and central Great Plains and regions immediately adjacent.
http://www.ianrpubs.unl.edu/epublic/live/eb3/build/eb3.pdf?redirected=true