Golden Sun

Camelot
Official developer's site, offering characters, psynergy, secrets, djinn, screenshots, and an online game.
http://www.camelot.co.jp/taiyo/index.en.html

CCG: Golden Sun
Offers cheats and hints.
http://www.cheatscodesguides.com/gameboy-advance-cheats/golden-sun-/

Game Software Code Creators Club
Contains Code Breaker GameBoy Advance codes.
http://www.cmgsccc.com/games.php?do=view&id=4929

GameFAQs
Includes, walkthroughs, maps, lists, FAQs, user reviews, message board, and secrets.
http://www.gamefaqs.com/portable/gbadvance/game/468548.html

GameSpot
Inclucdes general information, hints, movies, and late-breaking news.
http://www.gamespot.com/gba/rpg/goldensun/

GameSpy: Golden Sun
Offers release information and cheats.
http://gba.gamespy.com/gameboy-advance/golden-sun-/

IGN: Golden Sun
Preview, news, screenshots, and a review.
http://gameboy.ign.com/objects/015/015255.html