Skin and Texture sites :
Polycount - Q2 and Q3 skin site.
Terraforming studio - Skin and texture site.
Pandemonium - Great skin and model site.
Rorshachs Journal - Lots of nice Q2 and Q3 skins.
Galbraith Games - Skin and Texture for free.
Jinx skins - Q2 skin site.
Leviathen - Q1, 2 and 3 skins.
Shattered Art - Mostly Q2 skins and models.
Skinforge - skin art.
Skinner X - Costum quake2 skins.
StrangeFates Skins - Quake Skins and  Art.
Opiate's Texture Warehouse - Yeah your right it all about textures.

Map making :
Big house - Q2 and Q3 map reviews.
Deathmatch Heaven - Q2 and Q3 map reviews.
Fresh team - Q1,2,3 map makers (Damn good maps).
The ChemicalX Laboratory - Q1 and Q2 maps lots of fun.
The Mean Arena - skins, maps and textures for Q2 and Q3.
QuakeLab 2 - Map editor for ID Softwares Quake 2.
The Forge - Worldcraft tutorial site.
5th D-Group - utils, Maps and Mod site.

Leagues :
HellBowl - Q2 Swedish Battle League.
Champions league - Q2, Q3 and Sc League.

Tools :
Gensurf - Ground surface generator for maps.
Quark - Map editor and lots of other cool stuff.
Tread 3D - Great mapping tool.
QERadiant - Map editor tool
Quake Tools - aa The best quake tool site.
JamDonut - Texture tool a great one.
Rmg - Random map generator.

Community's :
Fragzone - Swedish game site.
3D files - Game, Driver and demo site.
Planetquake - Q1, Q2, Q3 all in one site (they got it all). 
Fileplanet - Game site.
BartepSoft - Q2 file and cool stuff site.
Q2netdoor -  Q2 map, File site.

Q2 bind sites :
Bind Palace - Q2 key binds (Ekke owns).

Q2 Mods :
Battleground - Team Dm mod (The best).
Q2Rock - Lots of gibb this mod rocks!.
Rocket Arena - Ra for Q1, Q2 and Q3.
Tourney - Orange smoothie creators of the Q2 Tourney mod.

Quake information and Programing  :
Quake Devels - The Quake Developers Library site.
Q2java - Code your mod in java  

Q2 Fun :
LamerKatz - Q2 lame clan numba1.
GameArt - The name says it all.

Q2 Clans :
uNCLe - Swedish Q2 Battleground clan.
Sub30 - Swedish Gaming Community.
Widow Makers - Swedish Q2 and Sc Clan.
Omega 12 - Swedish Party and Q2 clan.
Plus30 - Swedish oldman Q2 clan.
Clan noll8 - Swedish Q2 ctf clan (great dudes)