The majority of the songs in Guitar Hero II are cover versions produced by an in-house group of musicians, rather than the original artists. However, one of those musicians, Marcus Henderson, was able to contact Buckethead and involve him directly in the game's version of his song "Jordan", which is named as an homage to basketball player Michael Jordan.

After recording the song, Buckethead told Henderson in a voicemail, "I think this is one of the best things I've ever recorded in my entire life."
Contributed by Pogue-Mahone
When recording the cover version of "Laid to Rest" by Lamb of God, guitarist Marcus Henderson used the exact same amplifier and settings that Lamb of God guitarist Willie Adler used.

"One of the songs I worked on was "Laid to Rest" by Lamb of God, and what I did was freeze-frame their Killadelphia DVD right at the part that Willie Adler was talking about his rig, and I could see all of his settings written above his dials. So I zoomed in and wrote everything down, and called Mesa and asked them to send me a Mark IV, and I used that to record the song for the game."
-Marcus Henderson
Contributed by Pogue-Mahone
The Nilbog High School venue was named in homage to the movie Troll 2. The developers at Harmonix are fans of the cult classic and named the high school after the town the movie is set in.
Contributed by KidDivinegon
In the demo version of Guitar Hero II, the cover song for You Really Got Me includes the lyric where the singer says "Oh no no!" right before the guitar solo. For the retail version of Guitar Hero II, the "Oh no no!" was removed.
Contributed by Pogue-Mahone
When you finish the encore song 'Tonight I'm Gonna Rock You Tonight' by Spinal Tap in Guitar Hero II, the drummer will explode. This is a reference to the Spinal Tap movie where they said one of their drummers spontaneously combusted on stage.
Contributed by Pogue-Mahone