Are you looking for your state tax ID number, or for your employer's state tax ID number? Who is asking you for a state tax ID number?
You don't have a separate state tax ID number for yourself. Your tax ID number, for both federal and state, is your Social Security number, or your ITIN if you don't have a Social Security number.
Your employer's state tax ID number is in box 15 of your W-2, after the two-letter state abbreviation.
