If your ancestors aren't from Surry County, Virginia, there are more than a hundred other databases of marriage records at FamilySearch.org! Just scroll down and click on "All Record Collections" and then type the word "Marriage" in the Collection Name box in the upper left corner.
Early records may only contain the name of the bride and groom, plus the name of the person officiating. Marriage records from the 20th century often provide much more, including age at time of marriage, place of birth, home address, occupation, father's name and mother's maiden name. Marriage records can help lead you to birth records, and even more information about your family!