I was starting from scratch like you a few months back. Get the best you can afford, and DO get head tracking of some sort. It's a world of difference and your "situational awareness" (perhaps the most important thing) will increase a lot and speed up your progress.
Do your research... there are a lot of choices. I got the "Delan Clip". It's about 1/3 the cost of Trach IR, easy to set up ( I use "Open Track" free app) and I'm computer dumb. And it works great.Then order TrackIR for about $150 from Amazon and you're well on the way.There are cheaper alternatives to trackir if you are willing to do some work.
Good luck, and welcome.
I'm looking forward to when I'm not the greenest pilot in the ACG.