There was once a time, over a decade now, that I was a freshmen in high school. Back then i would have to get small amounts of weed from seniors. That period of time existed for about a year until my friends father got about 10 perc 5s for a medical thing, I bought 4 of them and took them. That was my introduction to pharmaceuticals. As you stated pharmaceuticals are kind of easy to get in high school because if you know 30 people odds are someone can get something.
Then junior year I had a random encounter basically I was at a friends house and couldnt get home so this kid that was in the area drove me home, i didnt know him but my buddy was like "your going that way anyway just take him to the top of the street" turns out he had an ounce of weed and sold small amounts. Mind you this was the first time i encountered someone with more then a half. So I started selling Gs and 1/8s. He would eventually get me shrooms and cocaine (very high quality he was upper class type kid with 1000s to spend)
Then one day i wanted L so i went to a "phil lesh and friends" show and took my g/f at the time and a friend to test the L. I bought 3 hits from some random dude gave them to my friend and stalked the guy at a distance. I then bought 50 hits once they were real, that was my introduction to L.
Next would be molly I first got that at a festival i went to alone as we went to the festival grounds the year before to buy 2 sheets of L, again an event orchestrated by myself. I was on 5 hits of L and decided it was a good time to candy flip having never rolled before.
But that is essentially the story right there. I am highly driven so like even my current molly connect i hunted that bitch down. I went to a show with the sole intent of getting a connect i spent forever finding it bought this middle man out, hounded the ever living shit out of him for week and eventually he gave me the connect i have for L, molly, weed, dabs all because i had the drive and desire.
Very few things were not my own doing. Even deemsters mescaline and others were all because i was like "fuck i want that" set my focus on it and eventually it happens. If you seek it it will find you when your ready for it.