Who handles complaints against the Credit Bureaus?

[PaKettle]

If I want to threaten the Credit Bureau with a complaint re their not fixing wrong information, who do I cite that I will report them to and who do I report them to? I have heard you can get them fined for false reporting but who does the fining? Is it the FTC or who?

Is there an online form for such complaints or do you have to write a certified registered letter? (Everyone always says a certified letter is best, but if you do some things on line you also do have proof of having filed them, depending on how their site is set up.)