Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada
A Catalog of the Diptera of America North of Mexico
By Alan Stone, et al.
United States Department of Agriculture, 1965
Cite: 105938
Nomenclature is dated, of course. One nice feature is range information.

This is online at USDA: Except for page 1202.

The above link is currently defunct
For now, you can access the PDF via this portal page.

Or, if you prefer, below is a direct link for the PDF file:

Warning: The PDF file is rather large.