If you talking about Reg Z, you can find the regulatory bodies in Appendix I:
"Retail, Department Stores, Consumer Finance Companies, All Other Creditors, and All Nonbank Credit Card Issuers (Creditors operating on a local or regional basis should use the address of the FTC Regional Office in which they operate.)
Division of Credit Practices, Bureau of Consumer Protection, Federal Trade Commission, Washington, DC 20580. "
I believe it would also be the FTC in most cases for the other Federal regulations. The FTC almost never initiates an examination - it would have to be triggered by consumer complaints.
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