Gov and search for withholding requirements for updates, online tools, and more information, including: Forms and Publications You can report most scams with Form 14242, Report Suspected Abusive Tax Promotions or Preparers.Submit Form 14242 online or mail or fax Form 14242 PDF. Send Form 592-V with a check or money order when you submit the nonresident or backup withholding amount on California source payments to us. When it applies, backup withholding requires a payer to withhold tax from payments not otherwise subject to withholding. 26 U.S. Code 7205 makes it a federal offense to intentionally provide false information on your withholding certificates or fail to supply the information. These forms contain information needed to complete federal and state tax returns. Please keep all tax related forms in a safe place. Our Investigation starts with your report. Write Us: Treasurer and Tax Collector, P.O. Box 512102, Los Angeles, CA 90051-0102 ; Visit Us: 225 North Hill Street, First Floor Lobby, Los Angeles, CA 90012.