Early in the day (earlier the better) make the cornbread, when done, place in a large bowl and break into large chunks. Also, I make my cornbread southern style, heating some bacon fat in the pan, as the oven heats, before pouring in the batter. (by the way, I'm doing this so early, and starving, so I usually have a small slice for breakfast - hey I'm human :) Lay bread slices on top ( you can tear those up a bit if you want). The purpose is to let it all dry out a bit. If you are cooking the turkey at home - take the giblets, neck etc out of the turkey, place in sauce pan, cover with water and bring to a boil, then simmer about an hour.
Remove the turkey parts from the broth, and add the diced celery and onion, bring to a boil again, then simmer about 30 to 45 minutes. If you aren't making your own turkey, use chicken broth or turkey broth (if you can find it)- Trader Joes has it, if you have one in your area, probably about 2 cans. Dump entire hot mixture of liquid and veggies onto the cornbread/bread in the bowl. Use a potato masher to start mashing it up.
Again if you are making your own turkey, at this point your turkey should be about done, because you would have started cooking it sometime after you finished the cornbread. Use a turkey baster to start taking turkey juice and transferring it to the bowl. (I use a cooking/turkey bag) to make my turkey, so I always have a ton of juice, enough for the dressing, and to make gravy.) After every couple of additions, mash it in some more. At this point you can use an electric hand mixer.
Mixture should be a bit soupy. At this point, add seasonings. I'd guess about ¼ teaspoon sage, and 1 teaspoon poultry seasoning. Taste, then add a little salt and a little pepper. Taste again, then decide if you want more poultry seasoning or sage - just remember a little sage goes a long way. Once it tastes like you want it, beat in the raw eggs, using the hand mixer, mix it on medium or high speed about 2 minutes.
Again, if you aren't making your own turkey, you can use chicken broth, you'll need to heat it up, and I'm not quite sure how much it would take, my guess is 3 cans, but have extra on hand just in case. The broth that comes in boxes is fine to use - I prefer to not use the swansons brand, it's not as rich as some of the other brands that come in a box. Just remember, again, this mixture should be pretty soupy - the raw eggs are what's going to make it set.
Generously butter a large casserole (if you don't have at least a 3quart casserole, you can use more than one, and pour the dressing mixture into that. Bake at 350 about an hour. It should puff up just a little bit, be a bit brown on top. Test for doneness by sticking in a toothpick, or you can use a butter knife, it should come out basically clean. Serve with Turkey and gravy.