Guitar Hero 2 cheats, codes, hints

Bonus basses
Complete stated number of songs in Co-Op mode to unlock the listed bass at the shop for Co-Op mode

Gibson SG Bass
Beat 10 Songs
Gibson Grabber
Beat 20 Songs
Gibson Thunderbird
Beat 30 Songs
Gibson Les Paul and skin
Beat 40 Songs
Hofner Bass
Beat every song
Lava Pearl Musicman Stingray
Get 5 stars on at least 10 songs
Cream SG
Get 5 stars on 20 songs
Natural Sunburst Gibson
Get 5 stars on every co-op mode song
Natural Maple Gibson Grabber Bass
Get 4 stars on all co-op mode songs

Bonus Guitars

Battle Axe
Complete the game on difficulty Expert
Casket
Complete the game on difficulty Medium
Fish
Complete the game on difficulty Easy
Snaketapus
Complete the game on difficulty Hard
Eyeball
Get a five star rank on all songs on difficulty Hard
The Log
Get a five star rank on all songs on difficulty Expert
U.S.A.
Get a five star rank on all songs on difficulty Easy
Viking
Get a five star rank on all songs on difficulty Medium

Bonus Song List
Complete the listed task on diffculty Medium or higher to unlock the listed song :

Tonight, I'm Gonna Rock You Tonight
Complete the first set and do the encore
Carry On My Wayward Son
Complete the second set and do the encore
War Pigs
Complete the third set and do the encore
Sweet Child O' Mine
Complete the fourth set and do the encore
Last Child
Complete the fifth set and do the encore
Stop
Complete the sixth set and do the encore
YYZ
Complete the seventh set and do the encore
Free Bird
Complete the eighth set and do the encore

Green Button trick

Put a rubber band around the green button,play it on hard so you don't have to push 5 buttons at a time

Grim Ripper plays Paul Gibson

Select Grim Ripper as your guitarist in Career mode, then exit Career mode.
Go to Quick Play mode, choose any song on any difficulty level. You can either finish the song or quit once it has started.
Now, go back to Career mode and the Grim Ripper will be playing the Gibson Les Paul with the Cherry Sunburst Classic skin. To make him play the Scythe again, simply select it in the Change Guitar menu.