IRS Enterprise Computing Center at Martinsburg, West Virginia Customer Service Section: Telephone 866-455-7438, M-F 8:30 am - 4:30 pm Eastern time or email mccirp@irs.gov
IRS Publication 1281, guide to backup withholding of federal income tax and the IRS "B Notice" requirements (note that this February 2011 edition of Pub 1281 shows an old 2007 version of the IRS Form W-9; the current Form W-9 has a revision date of December 2011 in the top left corner)
IRS Publication 1586, guide to the "reasonable cause" regulations including proposed penalties for filing forms with incorrect or missing Taxpayer Identification Numbers
IRS FIRE System for online filing, and filing extensions, for Forms 1099, 1098, 5498, W-2G, 1042-S. Copy this URL and paste it into your Internet browser: https://fire.irs.gov/firev1r/
IRS Publication 1220, specifications for electronic filing of 2011 Forms 1099, 1098, 5498, W-2G
IRS TIN Matching Program -- free validation service for Name-TIN furnished by a customer, vendor or other payee, available to those who file Forms 1099-B, 1099-DIV, 1099-INT, 1099-MISC, 1099-OID or 1099-PATR. The TIN Matching Program is within the general on-line IRS efile system. Tutorials for TIN Matching are available to everyone, regardless of whether you have registered yet to use the service. Tutorials include how to register, how to apply for TIN Matching, and how to use TIN Matching. To access the tutorials, follow these steps: 1. Go to the IRS eservices portal page 2. Click on the Registration Services link. 3. At the top of the webpage (next to Help), click on the On-line Tutorials link.