Firstly the website you've been reading seems a bit dated on a few points, but for the most part quite accurate. If you're interested in a really in depth analysis of how the mouse works have a look at:
www.funender.com/quake/mouse/index.html
1.1: To disable mouse accel it first depends on what OS you're running. The CPL mouse fix is only applicable to Windows XP based computers. If you're running windows 7 (I believe it also works for vista, not entirely sure) you will want the "mark c windows 7 mouse fix" found here:
www.filefront.com/17191014/MarkC_Windows7_MouseFix.zip
In addition to that mouse fix, make sure 'enhance pointer precision' is turned off as well.
For CS 1.6 you will need to add two launch options, "-noforcemaccel -noforcemparms"
My CS 1.6 launch options as they appear in "properties > set launch options", -noforcemaccel -noforcemparms -noipx -nojoy -freq 120
There is another phenomenon known as negative acceleration. This is most predominant in cases where a dpi of over 400 is used.
More info on raw input can be found in the following link under the headings 'neg accel' and 'input':
http://www.funender.com/quake/mouse/index.html
Only a few titles have inbuilt raw input functions (CSS through m_rawinput 1; and quake live through in_mouse 2 I believe). To eliminate negative acceleration through the use of raw input an external program known as Rinput can be used (Note: This is completely legal and not considered a cheat by EAC or VAC).
Rinput download:
http://fnatic.com/downloads/662/RInput-Win-Vista-7-Acceleration-removal.html
To use it, just run the rinput.exe and type in the name of the relevant games executable every time you run the program and hit enter, i.e. hl.exe, iw3mp.exe, etc.
1.2: True story, leave mouse settings on 6/11 otherwise you'll get weird skipping
1.8: Bit outdated, I'm fairly sure those commands are all relevant to the old pre-orange box version of CSS, there are now a couple of new ones as well.
Pasted from my autoexec.cfg (based on regnam's autoexec available from :
http://www.netcodeilluminati.com/forums/attachments/regnam-section-gratuite/89d1317859256-fichier-config-autoexec-high-fps-autoexec.zip)
m_customaccel "0"
m_customaccel_exponent "1"
m_customaccel_max "0"
m_customaccel_scale "0.04"
m_filter "0"
m_mouseaccel1 "0"
m_mouseaccel2 "0"
m_pitch "0.022"
m_yaw "0.022"
m_rawinput "1"
zoom_sensitivity_ratio "0.8"
sensitivity "3.5"
2.10: Finding you're own sensitivity is entirely up to you, the major issue with copying other people's sens is that it really comes down to whether you aim with your wrist or your arm and also the way you hold your mouse. If you do wish to copy someone's sensitivity that you know has a similar technique to you, you must also take into account what dpi they use as well (which for most top 1.6 players at least, is 400 by default).
Posted on Tuesday, 17th January 2012