In his youth, Tomaso played the piano for a dance orchestra in which he met drummer Dean Cornwell, who also became a famous illustrator and an influence on Tomaso's own style. Illustration historian Walt Reed wrote that Tomaso's "work mostly resembled Cornwell's in concept and broad brush style."
John T. McCutcheon, a family friend and cartoonist for the Chicago Tribune, encouraged Tomaso's artistic talent. Tomaso studied at the Art Institute of Chicago with J. Wellington Reynolds. He also studied at the Art Students League of New York with teachers including Dean Cornwell, Robert Henri and Harvey Dunn.
As an illustrator in New York, Tomaso worked for clients such as Granger Pipe Tobacco and frequently contributed to such periodicals as the Ladies' Home Journal and The Saturday Evening Post. He was at his best illustrating tales of high adventure, including the Albert Richard Wetjen stories about the Mounted Police of South Australia, or mysteries, such as Rex Stout's Nero Wolfe novel The League of Frightened Men. As a fine artist he was represented by the Grand Central Art Galleries and by Jean Bohne, Inc., in New York.
- Reed, Walt The Illustrator in America, 1860–2000. New York: Watson Guptill Publications, 2001, ISBN 0-8230-2523-3 page 253
- Joseph C. Lincoln, Rico Tomaso (illust.) "The Shale-Bastable Boots" - Ladies' Home Journal vol. LII (11): 23, 76–86 Nov 1935 Philadelphia: Curtis Publishing 9