Here is the full list of all 59 Guitar Hero III: Legends of Rock achievements worth 1,000 gamerscore.
Complete all difficulties in Career, buy everything from the shop and complete 100 online matches
Complete all songs as the back-up guitar player
5 Star all Co-op songs on Expert
Played through Career with Lefty Flip on and off
Win 500 Online Ranked matches
Earn a 2000 note streak in a Co-op match
Join Ranked Online matches and win 15 consecutive songs
Win 15 consecutive Ranked songs online using a standard controller
Host Ranked Online matches and win 15 consecutive songs
Score 750,000 on a song
Score 700,000 on any song in a Co-op match
Score 1,000,000 on any song in a Co-op match
200k on Cult of Personality without Star Power
Complete Co-op Career
Beat any song on the expert difficulty with the games sound options turned down to zero
Complete Career Mode on the Expert difficulty
Earn a 100 note Streak in Career or Quick Play
Earn a 250 note streak in Career or Quick Play
Earn a 500 note streak in Career or Quick Play
Earn a 1000 note streak in Career or Quick Play
Score 250,000 on a song
Score 500,000 on a song
Earn 5 stars on all songs on the Expert difficulty
100% a song
Buy all the Guitars from the shop
Buy all characters from the shop
Fail a song passed 90% completion
Earn a 200 note streak in a Co-op match
Get an 8X multiplier in a Co-op game
Buy everything from the store
Complete Through the Fire and Flames on Expert
Activate Star Power 3 times on Through the Fire and Flames on Expert
Earn a 150 note streak in a Ranked Online Battle mode match
Complete all Career difficulties
Complete a Career on the Easy Difficulty
Earn 5 stars on all songs on the Easy difficulty
Play through a career on the Hard or Expert difficulty using a standard controller
Complete Career Mode on the Medium difficulty
Earn 5 stars on all songs on the Medium difficulty
Refuse a boss battle
Use the Whammy Bar on every held note on Number of the Beast
Earn a 1000 note streak in a Co-op match
100% a song in a Co-op match
Score 500,000 on any song in a Co-op match
Earn 5 stars on all songs on the Hard difficulty
Complete Career on the Hard difficulty
Earn a 500 note streak in a Co-op match
Beat one of the creators of Guitar Hero 3 at their own game
Fail any song 10 times
Complete the tutorial
Buy all songs from the shop
Gold Star 20 songs on Expert
Hit 250,000 notes in Career
Earn $350,000 in career lifetime earnings
Complete all Co-op as the lead guitarist
Earn 100,000,000 points total in Career
Earn 5 stars on all Co-op songs for the Easy difficulty
Earn 5 stars on all Co-op songs for the Medium difficulty
Earn 5 stars on all Co-op songs on the Hard difficulty