I've made a site that pulls data from the official Bandai Hobby Site to browse released Gunpla kits. This should make it easier to find kits by grade, series, and the release year.
The site should auto-update daily. If there are any bugs or missing information, please feel free to send me a reply or DM! I'm trying to keep this DB as automated as possible, so any kits that aren't part of the Bandai Hobby Site list aren't going to be included. When a new series or grade is released, though, I'll need to manually update the translations and image mappings.
Dalong is another good resource, but I prefer the manual scans from Bandai.