Is there is a game/anime/manga which is in English in one form or another (either Dubbed or Subbed for anime or officially translated/localized or fan translated for everything else) which would be a good entry point into the series?
How about this youtube channele? You can watch promotional videos and radio programs that you can watch for free; original, Million, Cinderella, Shiny and SideM are all treated. Anime and specials are distributed depending on the time.
Of course, these are legal content operated by copyright holders.