Where do you find rabbit holes that are worth the time?

I’d start with a narrow question, then look for the underlying material: records, reports, research papers, or documents from the people involved. Commentary can help you find those sources, but check whether it represents them accurately and whether other sources support the same claim.

Try following competing explanations instead of following one creator. Keep a note of what’s directly documented, what’s an interpretation, and what would change your mind. If a claim depends on every contrary source being part of a cover-up, that’s a good reason to pause.

Libraries, academic search tools, public archives, and specialist books are good places to browse. Pick a subject you genuinely enjoy, and let the sources point you toward the next question. A rabbit hole is more rewarding when you can trace how its claims were built.