I can also provide some useful links to the Total War games series as well and here can you find more news about http://www.twcenter.net/forums/forumdisplay.php?f=331.

http://forums.totalwar.com/
- http://wiki.totalwar.com/w/Main_Page
- http://forums.totalwar.com/showthread.php/124-The-Medieval-Total-War-and-Viking-Invasion-FAQ
- http://forums.totalwar.com/showthread.php/118-Frequently-Asked-Questions-amp-Game-Fixes
- http://forums.totalwar.com/showthread.php/119-Frequently-Asked-Questions-and-Game-Fixes
- http://forums.totalwar.com/showthread.php/46-A-guide-to-the-guides-%28Empire-Total-War%29
- http://forums.totalwar.com/showthread.php/263-Guide-to-the-Guides-%28Napoleon-Total-War%29
- http://www.totalwar.com/en_us/totalwarbattles-shogun
- http://www.twcenter.net/forums/forumdisplay.php?f=735
- http://www.twcenter.net/forums/forumdisplay.php?f=736
- http://www.twcenter.net/forums/forumdisplay.php?f=1549
- http://www.twcenter.net/forums/showthread.php?p=9871125#post9871125
- http://www.twcenter.net/forums/forumdisplay.php?f=1893
- http://www.twcenter.net/wiki/Released_Mods
- http://www.twcenter.net/forums/downloads.php
- http://www.twcenter.net/wiki/Modding_Portal
- http://www.twcenter.net/forums/forumdisplay.php?f=734
- http://www.twcenter.net/wiki/Released_Mods
- http://www.twcenter.net/forums/showthread.php?t=483527
- http://www.twcenter.net/forums/showthread.php?t=92488
- http://www.twcenter.net/forums/showthread.php?t=477691
- http://www.twcenter.net/forums/showthread.php?t=477898
- http://www.twcenter.net/forums/showthread.php?t=443435
- http://www.twcenter.net/forums/forumdisplay.php?f=25
- http://www.twcenter.net/forums/showthread.php?t=406671
- http://www.twcenter.net/forums/forumdisplay.php?f=1448
- http://www.twcenter.net/forums/showthread.php?t=136409
- http://www.twcenter.net/forums/forumdisplay.php?f=1695
Mod recommendations
Spoiler
Lord Kaelin - http://www.twcenter.net/forums/forumdisplay.php?f=127 for Rome Total War, http://www.twcenter.net/forums/showthread.php?t=374565 for Medieval 2 and http://www.twcenter.net/forums/showthread.php?t=417435 for Medieval 2
Nefarious One - http://www.twcenter.net/forums/forumdisplay.php?f=867, a massive M2:Kingdoms mod
Elrond - http://www.twcenter.net/forums/showthread.php?t=341088 for Empire Total War
uberbanna - http://www.twcenter.net/forums/showthread.php?t=453038
Medivh - http://www.europabarbarorum.com/ (EB2 is WIP)
Lord Kaelin - http://www.twcenter.net/forums/forumdisplay.php?f=127 for Rome Total War, http://www.twcenter.net/forums/showthread.php?t=374565 for Medieval 2 and http://www.twcenter.net/forums/showthread.php?t=417435 for Medieval 2
Nefarious One - http://www.twcenter.net/forums/forumdisplay.php?f=867, a massive M2:Kingdoms mod
Elrond - http://www.twcenter.net/forums/showthread.php?t=341088 for Empire Total War
uberbanna - http://www.twcenter.net/forums/showthread.php?t=453038
Medivh - http://www.europabarbarorum.com/ (EB2 is WIP)
DarkOneVenzar has a tool for managing your Medieval2TW mods. Thanks for sharing this M2TW-mod tool.
Spoiler
For those who need to simplify the installation and removal of mods from their Medieval 2 launcher check out http://code.google.com/p/medieval2modinstaller/ program I wrote which makes it a bit easier. Despite the name the program doesn't actually install the mods, just installs them to the launcher. You do need the .NET 4 framework installed, but the client profile version works just fine.
For those who need to simplify the installation and removal of mods from their Medieval 2 launcher check out http://code.google.com/p/medieval2modinstaller/ program I wrote which makes it a bit easier. Despite the name the program doesn't actually install the mods, just installs them to the launcher. You do need the .NET 4 framework installed, but the client profile version works just fine.
How to install mods on Steam versions
Spoiler
Install the mod into this &--#60;path&--#62;\Steam\steamapps\common\&--#60;total war="" game=""&--#62;\data\ folder which create this &--#60;path&--#62;\Steam\steamapps\common\&--#60;total war="" game=""&--#62;\data\&--#60;mod folder=""&--#62; structure on your HDD
if the installation has more than one setup file just install it into the same folder like the first one and patches too
Install the mod into this &--#60;path&--#62;\Steam\steamapps\common\&--#60;total war="" game=""&--#62;\data\ folder which create this &--#60;path&--#62;\Steam\steamapps\common\&--#60;total war="" game=""&--#62;\data\&--#60;mod folder=""&--#62; structure on your HDD
if the installation has more than one setup file just install it into the same folder like the first one and patches too
Since http://www.gamesas.com/index.php?/topic/1305493-total-war-discussion-3/page__view__findpost__p__19788436 I realize that were no such list of Steam version games in the OP, but below they are listed and let me know if there is something to add or correct that game list.
Retail Version
- Medieval TW
- Medieval 2 TW
- Rome TW
- Shogun TW
- Empire TW
- Napoleon TW
- Shogun 2 TW
Please note that most retail games is also available on Steam except for Shogun TW and probably Medieval TW, because the older titles was development with either DX7 or DX8 for Windows 95/98 when they were released in the 90's.