Well, here is the good news: most major players in the Techno world are still around - they are alive and kicking.
So if you want to learn more about:
-An old 90s label
-A compilation series
-Legendary events that used to happen in your town
-Or elsewhere
-Famous DJs, producers, key figures
-Background stories to a release
-Rare releases
-Unreleased releases
-How the scene was "back then"
-If HC existed in your country, too
-Sleazy stories about the things that happened in the green room (no, wait, let's skip that one!)
Then the best way is to look up an artist/producer/DJ
And just send them a message, and ask them about the topic you research!
Think about it.
If a real journalist.
Is doing a documentary about the rolling stones, or oasis, or madonna, or anyone else.
First thing the journalist would do is to reach out to them, and talk to them!
The journalist for sure wouldn't just sit at home and browse the internet.
(Assuming the rolling stones are still alive when you read this text).
Many Techno and HC producers are active on the internet, even taking part in fan communities.
Of course you shouldn't kick the door down, hassle or annoy them!
Be friendly, polite, have some courtesy and taste.
Remember: *you* are the fan. These are your kings and queens. So have some respect, will ya?
And if an artist doesn't reply or doesn't want to talk to you.
Then shut the fudge up.
But if you reach out to people in a "journalistically sane" way.
Then a lot of people might be interested to work with you on your research.
Part 2
I already talked about some things in part 1.
Now here are things you should try to avoid:
To base your research on online sites or databases like Wikipedia or Discogs.
These are highly unreliable and incomplete. Anyone can add or delete information there.
Such sites can be a starting point for research - sometimes. But then you need to move on.
Discogs is a database that lists releases of labels, and even that info is often wrong, full of errors, or missing.
Beyond that, it does tell you nothing about the history or background of music scenes or genres.
I stress that, because I had people who told me "the first release tagged with 'speedcore' on discogs was x by y in the year z, and that means..." - no, it doesn't mean shit.
Anyone could have added that tag, or could remove it again. It gives you zero real information about the history of speedcore.
So, avoid these sites, or at least be aware that everything you read on there *could* be true, but equally it could be false.