Resources
Like any planner enthusiast, I spend far too much time on YouTube and reading blogs about planners. Here are a few of my favourites.
YouTube
YouTube has an endless supply of planner channels. I'm going to highlight two general channels, and a couple more niche ones:
For general planner walkthroughs, Amanda's Favorites is a great starting point. Her reviews tend to be consistent, with the same tests for each planner. Amanda's channel is more about giving information than strong opinions. It's the place to go for a detailed look at a planner you're considering, but maybe not for the spiciest hot takes.
Blogs
For productivity methods, nothing beats the Todoist blog. Todois is a todo list app, but a lot of their resources work equally well for paper planning.