How to join in the wp8 emulator sd card
-SDcard storage is read-only(which makes sense since it's not considered as a storage extension for apps.)
-You can only read/process file types you registered for in the app manifest.
The original questions still hasn't been answered: "Is it possible to connect the Emulator SD card, and if so, how". Personally I'd love a wiki article listing the things you "can't do on the Emulator that you can do on the device" along with links to related articles on things you can do. If exhaustive, would be a good candidate for the competition.
For the moment I never find the way to have SDcard "emulation" on the emulator. I am not sure that it supported by the emulator.
For new features of WP8 see: