Do you experience smoking other meats? If so, what have you done and how did it turn out? I would recommend brining the bird prior to cooking it.
Also, do you have any of Steven's books? Barbecue Bible has instructions for grilling a turkey, Beer Can Chicken has a recipe for smoking a beer can turkey, How to Grill teaches Cajun smoked turkey, and Sauces, Rubs & Marinades has a wonderful assortment of sauces and glazes for serving with the finished product.
On the upside...if the turkey is a disaster...you may never have to cook for the in-laws again.