There are two different tax identification numbers that are commonly referred to as "Tax ID Number".
This is a State requirement for Virginia. If you will be buying wholesale or selling wholesale and /or retail, more than likely you will need to file Form R-1 with State. Please contact the Virginia Department of Taxation at 804-367-8037, or register online.
Federal Identification (Employer Identification Number)
Form SS-4. This number is used to identify the tax accounts of employers, sole proprietors, corporations, partnerships, estates, trusts and other entities. You will need an Employer Identification Number (EIN) if you have employees, a Keogh plan, operate your business as a corporation or partnership or file a tax returns for either employment, excise or Alcohol, Tobacco, and Firearms. Visit the IRS website or apply online.