Report the employee to your state's new hire reporting agency. The new hire reporting program requires employers to report information on new employees for the purpose of locating parents who owe child support. For more information, go to the Administration for Children & Families website at http://www.acf.hhs.gov, which also provides the name and address of your state's new hire reporting agency.

Fill out Form I-9, Employment Eligibility Verification. U.S. Citizenship and Immigration Services (USCIS, formerly known as the INS) requires employers to use this form to verify that every employee they hire is eligible to work in the United States. (You don't have to file this form with the USCIS, but you must keep it in your files for three years and make it available for inspection by officials of the USCIS.) You can obtain the form online at http://www.uscis.gov.

Have the employee fill out IRS Form W-4, Withholding Allowance Certificate. On this form, employees tell you how many allowances they are claiming for tax purposes, so that you can withhold the correct amount of tax from their paychecks. (You don't have to file the form with the IRS.) You can find this form at http://www.irs.gov.