I feel like this is a very passive PROVE YOUR KNOWLEDGE! question - but I only feel that way because of it being anonymous. Oh internet. You have ruined me.
But to answer the question I get most of my information from books/years of education. If I am responding or writing something quickly I do google Japanese terms and what not, mostly to double check I’ve a.) got the right term and b.) spelled things properly.
When I write “academically” my main sources are indeed books.
EASY READING:
Japan: Its History and Culture
W. Scott Morton
J. Kenneth Olenik
Learning to Bow: Inside the Heart of Japan
Bruce Feiler
Japanese School Girl Confidential: How Teenage Girls Made a Nation Cool
Brian Ashcraft
Shoko Ueda
JTB’s Illustrated Book Series: Japanese Family and Culture
Japan Travel Bureau
Dreamland Japan: Writings on Modern Manga
Frederik L. Schodt
Any volume of Mechademia
MODERATE READING:
Mediated girlhoods: New Explorations of Girls’ Media Culture
Mary Celeste Kearney
Understanding Japanese Society
Joy Hendry
Adult Manga: Culture and Power in Contemporary Japanese Society
Sharon Kinsella
DIFFICULT AND WORDY READING:
Modern Japanese Culture
Yoshio Sugimoto
Poison Woman: Figuring Female Transgression in Modern Japanese Culture
Christine L. Marran
Becoming Modern Women: Love & Female Identity in Prewar Japanese Literature & Culture
Michiko Suzuki
Japanese Cybercultures
Nanette Cottlieb
Mark McLelland
Broken Silence: Voices of Japanese Feminism
This book has like 7 authors
Queer Japanese: Gender and Sexual Identities through Linguistic Practices
Hideko Abe
And just to be more-snotty-than-passive-aggressive HERE is a picture of the pile currently next to my computer. Plus The Walking Dead Vol. 15, evidently. Did I finish reading that? Oh shit. I don’t think I did.