6 links
ADnD Downloads
adnddownloads.com
Contains resources such as new spells, classes, and feats. Accepts submissions.
Descent into Depths!
descentintodepths.blogspot.com
Descent into Depths is an old school 1st Edition AD&D adventure run by the Infinity Group.
Heroes Only
angelo.freeshell.org
The site has adventures, new classes, races, monsters, spells, and new rules for the old D&D rules set.
Michael's AD&D Page
geocities.com
Contains zipped resources, information about a play-by-email game, and pictures.
Wizards of the Coast: Dungeons and Dragons
izards.com
Information about current and upcoming official products.