Well it's a big big rabbit hole that you can go down in multiple ways, most of which involve putting your faith in it and becoming really irritating and unstable. Some of the posters links in their second post are good starts but it's kind of a random mix of stuff. They linked to the wiki on Abrahamic religions as if that would give you some sort of summary of their occult practices.
Not addressing the veracity of the cosmological or ontological claims of any mystics, it's all some great sci-fi/fantasy and I call my hobby concerning it gonzo mysticism, since I enjoy inserting myself Hunter Thompson style into magical practice to see what it does regardless of if it 'came from ancient egypt' or is some **** made up by Victorian eccentrics. I am interested in the occult primarily because I am a 19 year old goth girl who likes weird history at heart, but also because I am interested in inducing altered states, especially non symbolic experience/nonduality type experiences as well as using systems of correspondence as a mnemonic system for art and generating meaning in real world experiences so that I can practice the skill of stepping away from it.
Here are some actually interesting links about magic and mysticism that aren't pushing some pathetic agenda:
The Hermetic Order of the Golden Dawn is the source of virtually all modern western mystical and magical traditions,
this is a good short summary.
John Michael Greer is a druid and writer 'whose work focuses on the overlaps between ecology, spirituality, and the future of industrial society.'
Alan Moore talking about his thoughts on magic
This book is a great summary of contemporary occult ideas I can send you a pdf if you want I think
As far as the NSE/ND stuff, there is obviously Buddhism, however I am the most interested in the non Sam Harrisy type modern neuroscience buddhism. It's reddit, but /r/streamentry has a lot of good technical discussion on this, and it seems that the most popular system of practice is from Culadasa and his book
The Mind Illuminated.
More interesting to me, but somewhat offputting because of the weird marketing, is Jeffrey Martin's
Finders Course. Based on the curriculum materials that I have been able to find, it looks like an attempt via correspondence course to (relatively) rapidly expose people to diverse traditions of meditation, based on the idea that it isn't that these traditions and their dogma are providing access to the supernatural conduits of energy that they describe, but that these systems describe a specific configuration of brain physiology which is common to all mystic traditions, and that a different method of attainment is likely to work for each person, with some being more effective in general.
These types of experiences coming from mindfulness practice are just about the gold standard of human well being as far as all those dumb rating sheets psychologists love, and seem to correlate to the spooky stuff described in history that doesn't involve plants or drinks etc.
I don't know if their methodology is nonsense or not since it isnt public yet, but since I have money coming out of my ears now I am going to do their next session (they just started one, probably this summer) and see if I can get them to give me a better look at what they are doing. They claim that 70% of participants experience cessation events and other transient non symbolic experience and that a good proportion of those people move on to persistent non symbolic experience, which they use after a year of non identification with the ego. I've experienced a good amount of these things trying different systems of meditation, so I would imagine that I would have good success doing the same thing in a systematic fashion in a cohort of other meditators. They are also recording biofeedback information now which is very exciting to me, as I have been waiting years to have enough money to rig myself up with wires while I get drunk/high/meditate/trip/****.
This lines up with my personal goals, in that I have been making plans to build a giant permaculture (though not by that name, because I hate it) ranch/preserve thing where rich people (I am talking members of this board and up) can come and experience low energy lifestyles growing the food they eat while also being exposed some sort of systematic evidence based protocol to induce non symbolic experience.
I figure that these experiences are the most likely event to convince people that they don't need personal attainment through consumerism, and that they are going to be happier growing their own food with some help from automation to make it less time consuming and painful so they can also spend time hanging out with other humans in natural settings. The marketing campaign for this is going to be my weird cartoons about mysticism that I am working on, the studio for which will be combined with the workshop producing all the carbon negative agriculture equipment I am obsessed with. If I can swing it, which is looking more likely all the time, getting rich people to chill the **** out and not do anything without worrying about the DEA is probably the biggest impact I could have on climate damage. Not that it will help, but still.
So, there's a bunch of stuff man, I hope you like it.
Epstein didn't kill himself.