Guitar Hero III: Legends of Rock Cheats

Various codes
Go to "options" and then go to "cheats." Now, cheats are entered completely differently in the third installment. You now have to strum with the frets on just like normal playing! Two or more notes in parentheses indicate a chord.

G=Green, R=Red, Y=Yellow, B=Blue, O=Orange

(BY) (GY) (GY) (RB) (RB) (RY) (RY) (BY) (GY) (GY) (RB) (RB) (RY) (RY) (GY) (GY) (RY) (RY): Air Guitar
OBOYOBOY: Hyperspeed
(RY) (RB) (RO) (RB) (RY) (GB) (RY) (RB): Performance Mode
(GR) (GR) (GR) (RY) (RY) (RB) (RB) (YB) (YO) (YO) (GR) (GR) (GR) (RY) (RY) (RB) (RB) (YB) (YO) (YO): Precision Mode
(YO) (RB) (RO) (GB) (RY) (YO) (RY) (RB) (GY) (GY) (YB) (YB) (YO) (YO) (YB) Y R (RY) R Y O: Unlock all songs in Quick Play

Through the Fire and the Flames
To unlock TTFAF, you must beat Career mode on any difficulty. Then, when the credits role, you will play TTFAF (note: you can't fail). From then on, TTFAF can be found in the bonus songs section.

Through the Fire and the Flames: Beat Career Mode on Any Difficulty

Unlockable Characters
Lou: Beat his Boss battle, Buy in Shop
Slash: Beat his boss Battle, Buy in Shop for $10,000
Tony Morello: Beat his Boss Battle, Buy in Shop for $10,000

Unlocking Additional Guitars
There are many guitars not in the store but are available for purchase after completing tasks.

Bat Guitar: Five Star every song in Career Mode on Easy
Jolly Roger Guitar: Five Star every song in Career Mode on Medium
Moon Shot Guitar: Beat Career Mode on Easy
Nemesis 13 Guitar: Beat Co-Op Career Mode on any difficulty
Rojimbo Guitar: Beat Career Mode on Hard
Saint George Guitar: Beat Career Mode on Medium