The radiostations found in GTA games, starting with the groundbreaking Grand Theft Auto III have always been appreciated by fans and you will no doubt be pleased to know that Rockstar are catering to your musical desires outside of the games as well.
In this blogpost Rockstar provides links to playlists with the radiostations found in GTA III, Vice City, San Andreas, Liberty City Stories, Vice City Stories, Chinatown Wars, and GTA IV (incl. Episodes from Liberty City), on both iTunes and Spotify.
If you listen to these while driving, keep in mind the police tend to frown at GTA style driving stunts.