Plug your SD card into your computer, now using the link above get a hold of SDLoad, firstly you have to format the SD card to either FAT or FAT16, if you can't do this return your computer to the store from which you bought it . After formatting it run sdpatch.exe through the command line as follows:
sdpatch.exe (drive letter):\
now copy SDLOADER.BIN to the root of the card, at this point you can load it up with emulators and what not as long as they are in .dol format . They can be in any directory as long as SDLOADER.BIN is in the root.
After installing the above insert SD card into SD card reader and plug into memory card slot A. Insert your action replay card into B and the disc into that place where discs go.
When AR boots up pick the USA flag and then ADD NEW GAME. SDLOAD is the game name and push done. Then enter (m) as the code name. Enter the following code
7YPR-RKZZ-MH6W5
D26A-PE4J-1XX2W
ZJHY-B1ZH-6P00G
Then select ADD NEW CODE and name it SDLOAD. Enter the following code
Select the code named SDLOAd and check the box next to it, press start and Open and close the lid of disc drive when prompted. Then SDLOAD starts up and you can take it from there!
The Code Process is a one time thing and from then on you can enjoy the world of Gamecube Homebrew and Emulators on your Wii Console easily and without Modification.
Emulators for Gamecube that will work this way include emulators for Snes, Genesis, GameBoy Advance, Gameboy Colour, PC Engine and Nes and also a port of Doom.
Enjoy Legal Homebrew and Emulation on your Nintendo Wii!