The majority of federal statutes governing immigration law are codified in the Immigration & Nationality Act (INA), located in Title 8 of the U.S.C., Aliens & Nationality, §§ 1101-1178.
Pertinent federal statutes can also be found in Title 6, Domestic Security; Title 18, Crimes & Criminal Procedure; Title 22, Foreign Relations; Title 29, Labor; and Title 42, Public Health & Welfare.