Link's Awakening

eLook
Cheats and tips.
http://www.elook.org/games/cheats/gbc/561.shtml

GameFAQs: Legend of Zelda DX
Codes, walkthroughs, and user reviews.
http://www.gamefaqs.com/portable/gbcolor/game/197769.html

GameFAQs: Legend of Zelda: Link's Awakening
Walkthroughs and user reviews.
http://www.gamefaqs.com/portable/gameboy/game/563277.html

GameSpot: Legend of Zelda: DX
Game features and review [8.7/10].
http://www.gamespot.com/gbc/rpg/legendofzeldadx/

IGN: Legend of Zelda: Link's Awakening DX
Game information, news, codes, and review [10/10].
http://pocket.ign.com/objects/010/010683.html

RPGamer: The Legend of Zelda: Link's Awakening
Game information, media, and walkthroughs.
http://www.rpgamer.com/games/zelda/z4/z4.html

The Wind Fish's Egg
A great site on Link's Awakening covering nearly every detail of both the original and DX versions of the game.
http://www.geocities.com/magikarp129/

Zelda 4 Glitches
This site is dedicated wholly to the glitches in Link's Awakening. Tricks, weird stuff, and secret worlds.
http://z4g.150m.com/