TakaraTomy’s Diaclone site
The official Diaclone content, and it is brilliant. Yay!
The downside is it’s not in English. Boo!
https://www.takaratomy.co.jp/products/diaclone/
Diaclone Genome Project
A fantastic attempt to preserve the history and legacy of the original Diaclone line.
https://diaclonegenomeproject.blogspot.com
TransFormerLand
A wonderful resource featuring scans of the original Diaclone catalogs, with translations. Essential for fans of both Diaclone and Transformers.
https://www.transformerland.com/blog/diaclone-toy-catalog-scans-translation-1980-in-the-beginning