Zelda.com

Contains frequently asked questions, parental information, and system information. [Requires Flash 4, available for download].
http://www.zelda.com/ages/

Nintendo.com

Includes FAQ, strategy, screenshots, and video.
http://www.nintendo.com/games/gamepage/gamepage_main.jsp?game_id=315

Game Winners

Contains cheats, codes and hints.
http://www.gamewinners.com/game_boy_color/LegendOfZeldaOracleOfAges.htm

IGN

Game information, news, and preview.
http://pocket.ign.com/objects/016/016041.html

Game Revolution

Cheats, codes, hints, or help from Game Revolution.
http://www.game-revolution.com/games/codes/gameboy/legend_of_zelda_oracle_ages.htm

GameFAQs

Contains links to pages with guides and FAQs.
http://www.gamefaqs.com/portable/gbcolor/game/31269.html

Zelda Elements

Box art, fan art, and FAQs.
http://rpgplanet.com/zelda/7.shtml

Jesse World

Cheat codes
http://www.jesseworld.com/Codes/gameGet.asp?platform_id=14&game_id=263

Game Boy Codes

Cheats and codes.
http://www.allconsoles.com/gameboy/games/thelegendofzelda.shtml

Ganons Tower

Walkthrough, story, art, review, rings, bosses, maps and items.
http://www.ganonstower.com/zelda8.shtml

Teamanti

Full walkthrough
http://www.teamanti.com/ages.htm

Temple of the Forest

Contains an illustrated walkthrough with items list and trading sequences.
http://home.hostultra.com/~templeoftheforest/

GameSpot

Links to game news and preview.
http://www.gamespot.com/gbc/adventure/legendofzeldaoracleofages/