Rotten Tomatoes

Links to reviews, information, images, and a forum.
http://www.rottentomatoes.com/g/KirbyNightmareinDreamLand-707931/

eLook

Contains a list of cheats.
http://www.elook.org/games/cheats/gba/320.shtml

GameSpot

Reviewed by Frank Provo [7.9/10]. Features screen shots, cheats, FAQs, and gameplay movies.
http://www.gamespot.com/gba/action/kirbynightmareindreamland/

GameSpy.com

Reviewed by Christian Nutt [72/100]. "A solidly-made, beautiful, and halcyon adventure that's a bit too simplistic for contemporary tastes." Includes screen shots.
http://www.gamespy.com/reviews/december02/kirbygba/