Is there any maintenance with the stones? Like, do you have to level them off from time to time? I saw one of the sharpening systems with some add on like that. I'm getting kind of interested in the stones now.
Well, if you're open to free hand sharpening then that is awesome. Nothing at all wrong with systems but I do prefer free hand sharpening.
I posted a thread here a while back about the minimum four stones people would put into a kit. Might search for it as it has some good recommendations.
There are a ton of different routes you can go. Some will be more specific to certain steel types and desired results and others will handle just about everything. There's as many opinions on what is best as there are options.
A course or medium SiC (think Norton Crystolon) and a medium or fine AlO (think Norton India) can handle most everything. Baryonyx (sp?) is owned by
@FortyTwoBlades and he has very popular stones as well and can make a recommendation. But, these types of stones all do wear and dish. Not as quickly as water stones but they do indeed wear. Diamonds will wear also. They don't dish but they do lose their abrasive over time.
If I really had to give a bare bones, best thing to start recommendation? I'd have to say a 300grit UltraSharp 8"x3" diamond stone and either a 600grit diamond or a Spyderco Medium bench stone. I like a strop as well but you can make one of those easily enough if you don't want to spend money (cardboard, denim, paint sticks, etc. can all be used). A bar of green compound (CrO) is pretty cheap and will last you like seven life times. It isn't great for super steels though so you might need to consider diamond sprays/pastes/etc.
I don't have a Spyderco Medium bench stone (though I might just get one) but they'll last forever and everything I've seen on them is that they produce a good edge.
In general, I like toothier, lower grit edges but there is a place for more refined edges as well.
Stick to larger stones. In the long run you'll be glad you did. I believe 8" is a really good balance. With the larger stones you can do a one inch pen knife or an 8" chef's knife. Much more versatility than the 6" options.
Your steels, your desired results, etc. will all be a factor sooner or later.
It is challenging but don't get overwhelmed or intimidated. That's easy to do when starting out. People make it out to be a mystical art and the sheer volume of choices and opinions can be a lot to take in. Working edges are not that difficult to achieve if you follow fundamentals and learn the basics of sharpening. As mentioned, a permanent marker is your best friend here! Know that a lot of what you see and hear is folks who already have the basics down and are simply diving deeper into the rabbit hole. It's a really deep hole if you want to keep going down it but it is not necessary to get acceptably sharp knives.
That's just scratching the surface and just my own rambling thoughts. There's a bunch of other ways you can go as well and be just as happy. The folks in this forum are awesome so never hesitate to ask questions.