After beating Hugh in BW2 for the first time, Bianca will show you around the Aspertia City Pokemon Center. The normal Pokemon Center music does not play, its something different. Where can I find this music?
I don't think you can find the music in the game again since it's a remake of the guide theme that almost every generation has. This theme is only played when the player is introduced to Pokémon Centers and/or marts. So, you don't hear this theme again unless you replay the games. However, this is the theme found online.