A recommended book for understanding the history of the FTC and specifically on its evolving role in enforcing privacy rights is Chris Jay Hoofnagle, Federal Trade Commission: Privacy Law & Policy (Cambridge Univ. Press, 2016). Main stacks: KF 1611 .H66 2016
A recommended article describing the FTC's development of a "common law" of privacy rights through its power to police unfair and deceptive trade practices is Daniel J. Solove & Woodrow Hartzog, The FTC and the New Common Law of Privacy, 114 Columbia L. Rev. 583 (2014).
The department of Health & Human Services (HHS) is responsible for the protection of privacy for health information under HIPAA. Within the HHS, the Office of Civil Rights is in charge of enforcing the provisions of HIPAA and the implementing regulations. This website of HHS is the main page for information on HIPAA protections and enforcement.
The Justice Department has the Office of Privacy and Civil Liberties (OPCL). This office protects the public by ensuring the department's compliance with numerous federal laws related to privacy, including the Privacy Act of 1974, the E-Government Act of 2002 and the Federal Information Security Modernization Act of 2014. The OPCL provides oversight and coordination of the privacy procedure of the department and all its components. The OPCL's website is a good source for examining the policies and procedures put in place by an agency to ensure its compliance with the law.