Alright I have a few questions since this is my first bow season and I've never used scents or calls

1. How do I know when the rut is coming? Stupid question, but never being out in the woods to see it what should I look for?
You will know when you start seeing rubs and scrapes which usually start to apper around Ocotober 20 something. At least here in WI
2. Our bow season starts in September in Wisconsin, what calls/scents should I use during early season? Just prior to the rut? During rut? Post rut? I'm looking to pick up some sort of call because I think that'll be part of the fun of bowhunting but I need to know what to look for
I would not use any scent or call in September. Maybe some light grunts if a buck is to far out but that's about it. I start using my calls and rattling in mid October thru November. I like the Primos calls but try some at the store and pick one out you like. I have a grunt tube and a can call. the can is doe in estrous.
3. What is the "best" time to target big bucks? Is it pre-rut or during the actual rut?
That is the million dollar question it depends on where you are hunting and how big of a buck you are talking about. You will have to spend time in a tree or in the woods to answer that question properly.

4. How long does the rut usually last?
Again ask 4 people get 4 differant answers it depends on how many does are in the area and what there cycles are like.

5. Are cover scents worth it or does good old fashion scent elimination work alright too?

I don't wear cover scents I use scent elimination stuff. It depends on who you ask. If one thing don't work try another. There is no 1 way to kill a deer. That is what makes it fun. Go play and see what works for you most of it is trial & error.

Good Luck