Most of the games in the Guitar Hero series feature a selection of songs ranging from the 1960s to present day rock music from both highly successful artists and bands and independent groups. Guitar Hero Encore: Rocks the 80s features songs primarily from the 80s, while Guitar Hero: Aerosmith, Metallica, and Van Halen feature music from the respective bands and groups that inspired or worked with the bands.
Many of the Guitar Hero games developed for the recent generation of consoles (Xbox 360, PlayStation 3, and Wii) support downloadable content, allowing players to purchase new songs to play in the respective titles. Songs each cost approximately $2 through the various online stores for the console's platform. Prior to Guitar Hero 5, downloadable content for earlier games will not work in other games in the series, save for songs from Metallica's Death Magnetic which were available for Guitar Hero III, World Tour, and Metallica. Existing World Tour downloadable content for World Tour will be forward-compatible with Guitar Hero 5 and Band Hero, and for a small fee, some songs from both Guitar Hero World Tour and Guitar Hero Smash Hits can be exported to both Guitar Hero 5 and Band Hero, limited by music licensing.Activision has also stated that they are considering a monthly subscription service to deliver downloadable content to user for future games. Guitar Hero World Tour introduces a music creation mode that will allow players to create and share songs (excluding vocals) via the "GHTunes" service, which has remained present in all other Guitar Hero games and Band Hero since its inclusion. The creation tools were improved with Guitar Hero 5 and Band Hero as to allow longer songs and other means of generating songs in real-time.
In the first two games and the 2007 expansion Guitar Hero Encore: Rocks the 80s, the majority of the songs on the main career mode set lists are covers of the original song; for example, a song may be presented as "Free Bird as made famous by Lynyrd Skynyrd". Guitar Hero III: Legends of Rock introduces a much larger range of original recordings, and World Tour featured a setlist that contained all master recordings. The covers throughout the games are mostly recreated by WaveGroup Sound who has worked before to create songs for Beatmania, Dance Dance Revolution, and Karaoke Revolution,[78] making small changes to the guitar portions to make them more adaptable for gameplay.Almost all of the unlockable bonus songs are songs performed by the original artist for the game (the only exception is the song "She Bangs the Drums" by The Stone Roses, which is featured in Guitar Hero III: Legends of Rock).
Prior to the release of Guitar Hero III: Legends of Rock, Activision has worked with the iTunes Store to provide more than 1300 tracks of Guitar Hero-related music across more than 20 compilations, including most of the tracks from the games in the series, called "Guitar Hero Essentials". These compilations, such as "Killer Guitar Solos" and "Guitar Anthems of the '80s", include songs related to but not contained within the Guitar Hero series. Dusty Welch of RedOctane has stated "Where there’s music, there’s Guitar Hero, and with iTunes, we are able to provide fans with a central location for downloading their favorite rock anthems." Following the merger of Activision and Blizzard, the new company announced that it is planning on creating an alternative to iTunes based on the Guitar Hero brand that would allow for downloading songs and their associated note tracks for the Guitar Hero games.