I know there's that American Mafia article but even that doesn't necessarily seem to be saying there was a formally structured and recognized family there. And even if it was, it would be the only source I'm aware of. You can look at the lists below, some of which have ones that never had a real family, and they don't have Omaha. For the record, there was also the Newark family that was absorbed in the early years. Same for San Diego - absorbed by LA post-Prohibition. And Bill Bonanno talked about a family in Birmingham early on. But he's the only source on that.


Valachi (1963)
Boston
Buffalo
Chicago
Cleveland
Detroit
Los Angeles
Milwaukee
New York (5)
New Orleans
Philadelphia
San Francisco
Tampa
Utica, NY


Frattiano (1980)
Boston-Providence
Buffalo
Chicago
Cleveland
Detroit
Los Angeles
Milwaukee
New York (5)
New Orleans
Philadelphia
San Francisco
Tampa
San Jose
Denver
Dallas
Kansas City
Pittsburgh
Pittston
St. Louis
Steubenville, OH
Connecticut (unnamed city)


FBI (1980)
Boston-Providence
Buffalo
Chicago
Cleveland
Detroit
Los Angeles
New York (5)
New Orleans
Philadelphia
San Francisco
Tampa
San Jose
Denver-Pueblo
Kansas City
Pittsburgh
St. Louis
Pittston-Scranton-Wilkes Barre
Tuscon
Rockford, IL
Madison, WI
Elizabeth-Newark, NJ
Springfield, IL


FBI (1988)
Boston-Providence
Buffalo
Chicago
Cleveland
Detroit
Los Angeles
New York (5)
New Orleans
Philadelphia
San Francisco
Tampa
Denver
Kansas City
Milwaukee
New Jersey
Pittsburgh
Rochester
San Jose
St. Louis
Scranton
Tuscon


Angelo Lonardo (1988)
Boston-Providence
Buffalo
New York (5)
New Jersey
Philadelphia
Pittsburgh
Cleveland
Detroit
Chicago
Milwaukee
St. Louis
Kansas City
New Orleans
Denver
San Francisco

Windsor
Ontario
Toronto
Montreal