Welcome. Here is a extensive list of DOOM sites.
Ranging from sites just like this one to forums centered around Doom.
ID Software
Planetdoom
Wikipedia: Doom
Wikipedia: Doom Engine
Doom Wiki
Planetdoom Forums
New Doom
Doom Wad
Station
Doom World
Doom Legacy
ZDoom
JDoom
Vavoom
TeamTNT
New Doom Forums
Old Doom
