D&D/d20 links

Official sites and portals

The Dungeons and Dragons homepage, at Wizards of the Coast.
The d20 System homepage, also at Wizards of the Coast.
EN World -- still the best place on the web for general D&D and d20 info.
RPGnet -- RPG news, reviews, and discussions. Not restricted to D&D or d20.
The RPG Site -- gonzo RPG commentary and discussion. I doubt they really want to be called "official", but what the heck.
The d20 System Reference Document -- the D&D, er, I mean, d20 system rules online, courtesy of WOTC. That's right, you don't even need the rulebooks to play D&D anymore! Well, in theory anyway.
d20srd.org -- another place you can get the SRD, but very nicely formatted and hyperlinked.
The Open Gaming License -- where Wizards promises not to sue you if you publish fan material relating to D&D. Sorta like what's on this page.

E.N.Publishing -- the publishing arm of EN World.
Montecook.com -- Monte Cook's website, and home of Malhavoc Press, publishers of Iron Heroes.
Necromancer Games -- publishers of d20 modules, and an affiliate of Sword and Sorcery Studios in a vague, unspecified manner.
Paizo -- publishers of Dragon and Dungeon magazines.
Sword and Sorcery Studios -- creators of the Scarred Lands campaign setting and sourcebooks, and an affiliate of White Wolf in a vague, unspecified manner.

Aquela.com -- James Wyatt's personal roleplaying site. JW is a writer at WOTC.
Mearls' Journal -- Mike Mearls' blog. Mearls is an ex-freelance designer, the guy who wrote Iron Heroes, and now busily killing sacred cows at WOTC.

The Arr-Kelaan Software RPG tools page -- where you can get Hexmapper. It hasn't been updated since 1999, but it still works fine.
The Hexmapper Haven Yahoo group -- subscribe for tips, maps and more custom tilesets.
Corel -- the company that took over Jasc, makers of Paint Shop Pro.