Some fans created a Japanese LocoRoco Wiki. I don't know if there is an English Wiki anywhere yet. For those playing the game and trying to find items for the Loco House or Loco Editor the Japanese LocoRoco Wiki includes a per world list of what items can be found in each stage and what pieces can be found in the mini games. It's not complete yet but it is a place to start.

There's also a screenshot bbs and someone made a Loco House, Loco Editor upload area. Note that unfortunately Loco House houses and Loco Editor levels are not tradable across regions.