How can I learn more about conspiracy theories?

Conspiracy belief is studied seriously in psychology, sociology, political science and history. There are peer-reviewed journals, university courses and decades of research on why the beliefs form, who holds them and what they do to political behaviour.

Starting here rather than with the theories themselves gives you a framework before the content, which is the right order.

Richard Hofstadter's 1964 essay on the paranoid style in American politics remains the standard starting point. Later scholarship on rumour, moral panic and misinformation builds directly on it.

Reading how earlier generations panicked about earlier enemies is the fastest cure for assuming the present is uniquely compromised.

Where a theory concerns a documented event, the documents usually exist. Royal commission reports, coronial findings, declassified archives, Hansard and court transcripts are public in Australia and often searchable online.

Primary sources are less satisfying and far more useful than summaries of them.

Fact-checking organisations are useful but not infallible, and they have their own institutional positions. Read their reasoning and sources rather than only their verdict. A good check shows its working.

Pick one claim a month. Trace it to its origin. Write down what you found and what remains unresolved. After a year you will have a method rather than a set of opinions, and the method transfers to everything else you read.