You will need to plan ahead if buying a frozen Turkey: it can be catastrophic to find that the only turkey available for your intimate four-person dinner is a 26-pound glacial beast.
A frozen turkey needs to be defrosted. The preferred method is to defrost it in the refrigerator. (Yes, the one filled with the rest of the holiday fare.) Allow one day per 5 pounds. A 15-pound turkey will require three days to defrost thoroughly.
To prepare the turkey for roasting, first remove the giblets! Not only is it disconcerting to find these paper-wrapped lumps when carving the bird, but you may also wish to use the giblets in your gravy or stuffing. Next, rinse the bird inside and out. Pat dry with paper towels. If you are stuffing the bird, stuff it loosely, allowing about ½ to ¾ cup stuffing per pound of turkey. Brush the skin with melted butter or oil. Tie drumbsticks together with string. Lastly, insert a meat thermometer into the thickest part of the thigh. The thermometer should point towards the body, and should not touch the bone.