I made available at this site photographs of color originals of the plates bearing sharpshooter species of the following works. Just follow the links.
1. Victor Signoret. 1853-1855. Revue Iconographique des Tettigonides. Annales de la Societe Entomologique de France.
2. William Fowler. 1900. Biologia Centrali-Americana, Insecta Rhynchota, Hemiptera-Homoptera. Dulau & Co.
(Recently, digital copies of the whole Biologia-Centrali Americana was issued electronically, due to a joint project by the Smithsonian Institution and the Natural History Museum)