The first settlement here in America was at Jamestown. The endeavor to settle the colony and ultimately America was funded by investors of the Virginia Colony. These investors controlled all the claims to land in the colony. In order to achieve return on this investment, in 1618 the Virginia Colony authorized the headright system. This system provided 50 acres of land to each individual brought to Virginia. Until 1699, this was the only means of obtaining a land patent in the New Virginia. Anyone that paid for his own passage to America got 50 acres of land. Virginia planters also got 50 acres of land for each slave that was brought to America. Wealthy individuals would pay the transport of indentured servants to America. The indentured servant would work and improve the land for 5-7 years at which time they were expected to move into the unsettled frontier where they could then purchase land, often on credit. The wealthy not only acquired land, but they also got it cleared and made suitable for growing crops and tobacco, all for the price of a passage. The indentured servants though, also became landowners by the settling of the open frontier. After 1699 the Colony began to sell headrights of 50 acres for 5 schillings.
When looking for land grant records, much information can be obtained from the Library of Virginia website.
Don't forget that Kentucky and West Virginia were also a part of Virginia, and their lands fall under the headright system. Another thing to remember, the areas between the Potomac and Rappahannock Rivers did not fall under or recognize the headright system, and so they kept separate records. Lands in this area were called proprietorships. In 1649 King Charles gave this land to seven of his supporters, one of whom was Lord Fairfax. Click her for a resource on Northern Neck research.
Land records can provide much fruitful information, but many researchers avoid them because they find them intimidating. The key to understanding land records is to research them first to understand them before you search the actual records themselves.