If you need to cook your turkey in the next 24 hours and it's not thawed yet, your best bet is probably to thaw it in the microwave oven. Check your owner's manual for the size turkey that will fit in your microwave oven, the minutes per pound, and power level to use for thawing. Remove all outside wrapping from the turkey and place on a microwave-safe dish to catch any juices that may leak. Cook your turkey immediately after thawing it in the microwave. Do not refreeze or refrigerate it before you cook it.
Click here for more information from the USDA on preparing turkey.