I started playing Hatsune Miku: Live Stage Producer.
It's kind of like THE iDOLM@STER, except there are only a couple of songs (until you fork out money), only one mini-game (for live shows) and only one idol. But hey, the one idol it does have is the cutest!
At the time I started playing, the sole wiki in Japanese was devoid of any useful information about the game mechanics, so I started this site. I am incorporating any information which the wiki shows before we have discovered it for ourselves, but in contrast with my site for THE iDOLM@STER 2 (which is just a straight translation of an existing wiki), for the most part, this site is original research.
If you want to help, for the time being you should track down Omochikaeri on Rizon IRC.