WoW Classic Raid & Dungeon Tier Sets Gallery
Blizzard originally made these post-1.9 renders of each dungeon and raid tier set and had them up on the official website back in the day. I think they look beautiful and give a very good representation of what each armour set looked like on every race/gender/class combination.
I built this simple filter tool with which you can browse through each of the sets, selecting your race, gender and class to filter the gallery, so that all of these images were in one place and accessible as they were on the original WoW Site. Enjoy!
By the way, if you want access to all of the original image files in bulk, you can download (.zip 20 MB) the whole pack here. There are 401 images in total.