I had a spectrum, and found a comic shop that had old 80s computer magazines that taught assembler. I also found a z80 compiler via obscure pen pals via small ads in the games magazines. Edge of the seat stuff, but the feeling of accomplishment was astonishing when you actually did something. I think the bar is so high for bedroom coders these days and they're always getting weird drag n drop languages pushed at them, which just stifles creativity (imho).