If you're asked to fill out Form W-9 (Request for Taxpayer Identification Number and Certification), it's because the business or person hiring you needs your name, address, and Social Security or tax identification number for payroll and tax reporting purposes.
TurboTax doesn't include the W-9, as it isn't filed with the IRS. Just download it from the IRS website, print it out, complete it, and then give it to whomever asked you to fill out a W-9.
