Here's a playlist of all special episodes: https://www.youtube.com/playlist?list=PLoNILXkbAYWLtkHUoEorenmyHt6yblFCw

Here's a different playlist containing nearly everything (not yet updated with the seasons that are still in the process of being released, so AUS S5 and the very newest UK series): https://www.youtube.com/playlist?list=PLj3wnRdyoKVRM9DqNzJnXD6XORLla6LxK

There also the pre-season interviews that are a special task in itself.