Atari 5200

AGH Museum: Atari 5200 SuperSystem - http://www.atarihq.com/museum/5200/index.html
Images of hardware, peripherals, and game boxes.

AHS: Atari 5200 SuperSystem - http://www.atari-history.com/A5200.html
History and images of the system and peripherals.

Atari 5200 Frequently Asked Questions - http://www.atarihq.com/5200/5200faq/index.html
General, cartridge, hardware, peripheral, technical, and repair information.

Atari CX-5200 - http://www.classicgaming.com/gamingmuseum/5200.html
Specifications, overview, and pictures.

Caféman's Atari 5200 SuperSystem Features - http://cafeman.www9.50megs.com/atari/atari5200.html
Descriptions, game reviews, scans, and screenshots.

Game Winners - http://www.gamewinners.com/A5200/
Cheats, codes, hints, walkthroughs, and FAQs.

Ozyr's Atari 5200 Instruction Archive - http://www.ozyr.com/a5200/a5200.html
Instruction manuals.