So to get it you'll need, you guessed it, a hacked Wii console, from which to make a copy of the NAND. Once you have your patched ISO/WBFS, then you're mostly good to go.
The community servers are hosted courtesy of Wiimmfi, and to connect to them you'll need to patch your game. If you absolutely need to play Dolphin with Wii, then there's only way to do it, and that's online play via community servers (Nintendo shut down the official servers for the Wii a long time ago).