The LBA entry on the Open Directory Project, it contains a lot of links to other LBA related fan sites and projects.
The Encyclopedia Twinsunica is, as the title gives away, a encyclopedia about the world of Little Big Adventure.
Its goal is to document every aspect of the world just like a normal encyclopedia would, but from the viewpoint of the game world.
An overview page of the LBA series games that have an entry on MobyGames.
MobyGames is an online database for computer games, much like IMDb is a database for movies.