Taurus,
First I would bring with you a cushioned seat of some kind... Turkey hunting includes sitting for long periods of time so you want to be as comfortable as possible! Next I would suggest using a blind if your allowed to do so in your state.
When it comes to a particular call I would suggest buying one of each and practicing with them. This will accomplish 2 things... first you will learn how to use them and second you will decide which calls you like better. As for myself I prefer box and mouth calls. If your willing to spend a little extra money on a call try to purchase "custom" made calls... nothing against calls that are massed produced but I purchased a "custom" box call this past spring and absolutely love it! I also recommend purchasing a few locator calls... Owl hooter, Crow call, coyote call to assist in locating the gobblers... I will never forget when I used an owl hooter and had a gobbler respond... It was music to my ears!
When it comes to ammo there is so much stuff out there that you need to determine what load shoots best out of your gun... I have an 835 that shoots winchester 3" number 5 loads the best. I have no question that out to 50 yards I will kill a bird cleanly and I suspect that I can shoot out to 60 yards if I really wanted to...
I hope my 2 cents has helped you and I wish you lots of luck!!!