The Department of Justice has a list of contacts here:
http://www.justice.gov/actioncenter/report-crime#whitecollarReport Antitrust concerns
888-647-3258 or 202-307-2040
Report Antitrust violations associated with Recovery Act funding
FBI Corporate fraud hotline
888-622-0117
Reporting Intellectual Property Crime
Public corruption: submit an FBI Tip online or call the FBI Local Corruption Hotline