Normally I get about one to three turkey carcasses during our Thanksgiving season so if there are enough I'l get my biggest stock pot and cook up a big pot of turkey stock. If not, they go into the freezer with the chicken bones I collect when deboning thighs and such. I pick off the meat, seal it in a Food Saver bag and freeze it separately in smaller batches, as you never know when you'll get a craving for a chicken or turkey sandwich.
Once I have enough I just follow the classic Julia Child recipe for stock and let it cook overnight or a bit more. I've mentioned before that a neat trick of hers for adding flavor to a stock is to roast the bones first. It darkens the color but adds a lot of body and taste as well.
I'll roast chicken and turkey bones till they are dark golden brown in general, but with beef bones there's an additional trick: slather them with tomato paste and roast them till they are dark brown. This is another Julia Child tip and it works really well. The tomato paste cooks to a dark brown and adds a lot more color without making it taste like tomatoes if you roast them long enough.