Secret of Mana (English version name of Seiken Densetsu) is an “Action RPG” game on Super Famicom (or, outside Asia, Super NES) by Square.
Seed of Mana is a fantastic fansite of the game. Contains artworks and musics from the game, history, news, and links. As well as a SNES emulator + ROMs. Another nice fansite is Mana Knight’s.
GameFAQs has also more info about Secret of Mana (Seiken Densetsu 2) and Secret of Mana 2 (Seiken Densetsu 3).
Note: The English name of the first Seiken Densetsu is Final Fantasy Adventure, available for GameBoy. Legend of Mana is Seiken Densetsu 4, PlayStation.