Welcome to the board and welcome to turkey hunting!! You will quickly become addicted!!
First, the simplest call I can think of to use is the pushbutton call. They are easy to master and are very effective. A box call and a slate are also fairly simple to use and easy to master. Some people use diaphram calls, but they can be more difficult to get good with. My suggestion, though, would be to get 1 or 2 calls and practice hard with them before you try to tackle too many calls. A tape of wild turkey vocalizations would also be a good idea. No sense in practicing a call when you don't know what it should sound like!!

As far as decoys, they have their place and time. Be careful when using them on public land. But a single hen decoy can be effective most any time and a jake decoy with the hen can be effctive early in the season.

As far as time of day, check your state regs. Some states only allow you to hunt turkeys until noon, so the morning may be your only option. Most of the time though, the gobblers are most vocal in the first hour or so in the morning.

I hope this helps!!

Good luck!!

Slice