Well, there's a couple of elements to the PC question.
Here's the huge one: Things like what I've shown here are extremely uncommon on Mac. Thanks to Microsoft, 99% of gaming and similar things are Windows only. Most devs dont even CONSIDER putting things on Mac, because it's a ton of effort for next to no benefit... they just dont have the resources to do it. Or the desire, or a way to even test it (as most devs dont have Macs themselves). Which also means that Macs in general typically arent exactly built for gaming, or graphically intensive programs. Typically, most Macs are essentially business machines, if that makes sense.
Now, here's the other aspect of it: It might not be as crazy expensive as you think, to get a PC that can do it. Understand, a hyper-expensive PC like what I use is not an absolute necessity for this; I did that simply because I could. I had the resources to do it and I knew full well I'd be using the thing *frequently*, so... yeah, that's what I did. Gaming... and thus, graphically intensive programs... well, the accessibility of them has changed a whole bunch in the last couple of decades. Once upon a time, you needed to really shell out the big money to get a PC that could handle gaming. But now? Nah. Tech has advanced enough to make it so that you can get a machine capable of Doing Things without having to pay out the nose to make it happen.
However: I, myself, am *terrible* with hardware. I'm talking like, "cant even install a RAM stick without breaking the entire machine" sort of terrible. My PCs are typically specifically built or chosen... by the tech guys at the local Fry's who know this stuff. I tell them what I want, what I'll be using it for, the sorts of programs it'll be running, and they make all the selections and I typically just roll with it. So... yeah, you dont want me trying to point you at specific tech bits. Instead, I'd strongly suggest heading over to the Oculus Reddit, and asking there. There are plenty of tech-oriented people who know all the right stuff. Simply tell them what your budget range is and that you want to get a PC that can do all the cool VR stuff, and they'll not only help you figure out WHAT you need, but also WHERE the best place is to get it from. Simply be very detailed with your questions, and dont be afraid to question further if you get an answer you dont understand. If for whatever reason that Reddit section doesnt help, I can always give you alternatives. But for now, I think that's the best place to go.
The things *I* can help with are software issues, but of course, that's of no use to you until you already have the device. I am willing to assist with that though, whenever you might have the setup ready. There are certain specific games/programs that do require a bit of extra setup to function and can be a little confusing. I'm good at dealing with that sort of thing. I can also offer suggestions and such for new games/programs/whatever, based on your interests and stuff you already like. Again though, that's once you have it. But feel free to message me at any time.
Aha, I actually do have a solution for this.
Well, there's two aspects:
1. Some games/whatever work just fine from a sitting position to begin with. That crazy neon thing I showed? Zooming all over the place and shooting monsters and all that? I sit in my spinning desk chair the whole time. But even the spinning of the chair isnt REALLY necessary, I just like to do it when turning. It's the same for the 80s program, I always sit for that. Google Earth and the nature thing, totally fine for sitting at all times.
2. But, some things wont quite work. At least, not without doing something. Did you see that picture of the arcade program I showed in my initial post? You cant do that while sitting in the default manner... the machines are too tall! But, there's a trick to it: You can simply change your height, setting it such that the program in question thinks you're fully standing up. Essentially, dragging the entire world lower, to meet your sitting height. This solution is not 100% perfect: If you drop some virtual object on the floor or something and want to pick it up, you wont be able to reach all the way down to grab it, since you're effectively "floating" above the floor. After all, you cant reach your real hands down through your ACTUAL floor, yeah? For some programs this is not at all an issue (No Man's Sky for instance, you dont really pick things up but instead interact with them by pointing that beam thing, so you dont need to reach down to the floor to do things) but others it can be more than a bit annoying. But not all that often. How to do it is something I can explain to you when the time comes. Not actually hard.
Anyway, there's a couple of other things that you might want to see, which can give you more of an idea of some stuff you can do in VR and how it works.
First:
This one shows off a common feature of VR programs, which is a "comfort mode". These exist to reduce the chances of side effects on newer users. In this video I'll show off normal movement, as you've seen before, and then switch the comfort thing on, and you can see what it does. The effect it produces prevents dizziness. LOTS of programs have all sorts of comfort options. It's important to know what options a program has before buying/downloading it.
Do you like art? Drawing, painting? Then you might LOVE this. This is Tilt Brush. It's another one by Google, and it's free! It's also bloody amazing! Just... just watch it. You'll get the idea. It is far from the only art program out there, too. There are others that are about creating 3D objects, or sculpting things, or all sorts of stuff. This program is one that I use if I wanna really show off the sheer POTENTIAL of what VR can do.
If you have a Steam account, you can access this. This is the central VR hub in Steam. The area I start in is my own customizable room. But from there, I show off some of the many, MANY user created environments that I have downloaded. Some places are actually created using photogrammetry (like that snowy place), while others are created through traditional 3D modelling. There's all sorts of stuff that can be done here. I do apologize for the bit with the Mario stairs, I got frustrated trying to go up them and was stubborn about it. Still, lots of cool stuff shown here. I could spend HOURS showing off things I've found in this. Google Earth sure aint the only way to explore interesting places.
Lastly, this is the arcade program I've mentioned before. I finally got the blasted thing to record it.... without sound. Bah. But the reason I'm showing this, is because it lets me show off a lot of common interactions that are found in VR; teleporting, picking up and throwing objects, activating things, and other stuff. I also show a couple of the games but they dont work quite right while the recording software is running.
Hope some of that helps, or gives you some ideas as to stuff you might want to look into!
Nah, it's not any trouble. I have nothing but free time all the time. And this IS one of my special interests. So I enjoy showing it off to people. And I really do think this tech could be very beneficial for many who are on the spectrum.
Besides, the things are fun to mess with while I'm doing the recording.
If there's any other questions you should have, feel free to ask! This is an enjoyable topic for me.