If you're purchasing from a dealer (FFL), then you'll want to go ahead and get your VA driver's license or state ID card, and you'll also need another document to show proof of residency. Purchasing requirements outlined below from the
Virginia State Police website:
Identification and Residency Requirements
A primary and secondary form of identification must be presented to the firearms dealer at the time of purchase of any firearm except an antique weapon, or replica of an antique weapon.
Primary Identification
The primary form of ID shall consist of a valid photo-ID form issued by a governmental agency of the Commonwealth or of the prospective purchaser or transferee’s home state that denotes the individual’s name, race, sex, address, and date of birth. Where the primary form is a photo-ID issued by the Virginia Department of Motor Vehicles (DMV), the dealer shall not transfer a firearm to the prospective purchaser until 30-days after the date of issue of an original or duplicate driver's license unless a copy of his/her DMV driver's record is presented showing that the original date of issue was more than 30-days prior to the attempted purchase.
The primary form of ID for a non-Virginia resident, for the purchase of a rifle or shotgun, must consist of a valid photo-ID issued by a governmental agency of the prospective purchaser’s home state that denote the purchaser’s name, race, sex, date of birth and address. Federal law prohibits the sale or transfer of a handgun to a nonresident of the state in which the handgun is being purchased.
Secondary Identification
The secondary form of identification, for Virginia residents and residents of other states, must show an address identical to that shown on the primary form of identification. Some acceptable forms of secondary ID are:
a current lease,
evidence of currently paid personal property tax or real estate tax,
a current utility or telephone bill,
a current voter registration card,
a current bank check,
a current passport,
a current automobile registration and
current hunting or fishing license.