The musicians spoofed are: Johnny Cash, Bob Dylan, Ray Charles, David Bowie, Roy Orbison, Queen, Meat Loaf, David Crosby, Jim Morrison, Harry Chapin, Don McLean, Elvis Presley, The Cars, Christopher Ward, Nelly, Tim McGraw, The Beatles, Brian Wilson (during his "SMILE" album period), Stevie Wonder (who lost his sense of smell after a 1973 car crash), and Michael Jackson (with a monkey and giraffe as house pets).
John C. Reilly sang every song on the soundtrack, and played guitar on most of them.
The photograph on the poster is based on the famous Joel Brodsky photo of Jim Morrison, which was used for the Best of The Doors album cover.
Dewey Cox's audition, at which he sings "That's Amore," is a reference to Elvis Presley. He showed up at his audition for Sun Records wanting to sing like Dean Martin. Sun owner Sam Phillips refused to record him until he and three members of the Sun house band started jamming on Arthur Crudup's "That's All Right, Mama," which became Elvis' first record.
The screenplay was featured in the 2006 Blacklist, a list of the "most liked" unmade scripts of the year.