From the VA State Corporation Commission: "Sole proprietorships are not required to register with the SCC".
The VA state tax office and IRS will be happy to accept tax payments filed as a sole proprietor.
Now, if the person plans on having co-owners, hiring employees, subcontractors, wants a business checking account,requires some kind of legal protections, needs to have an office, etc. Then they may want to incorporate, form a general partnership, or limited liability company. In those cases, registration is required. They can read
http://www.yesvirginia.org/pdf/guides/2005EstBusGuide.pdf
A guy selling web design services on his own does not need a license.