To activate the Guitar Hero 3 - Legends of Rock, "Unlock All Songs" cheat for the Wii, go to the Cheats Menu and enter the following codes.
(Yellow Orange),
(Red Blue),
(Red Orange),
(Green Blue),
(Red Yellow),
(Yellow Orange),
(Red Yellow),
(Red Blue),
(Green Yellow),
(Green Yellow),
(Yellow Blue),
(Yellow Blue),
(Yellow Orange),
(Yellow Orange),
(Yellow Blue),
Yellow,
Red,
(Red Yellow),
Red,
Yellow,
Orange