Here is a download link.
How To Install.
1.)Download "Counter-Strike 1.6 Source.rar" archive in provided above link.
2.)Once it finished downloading, download "WinRAR" program. Here is the link of this "WinRAR" program.
3.)Once the downloading of the "WinRAR" program finished, install it.
4.)Open the downloaded before "Counter-Strike 1.6 Source.rar" archive with "WinRAR" program.
5.)You will see the "game" folder in this "Counter-Strike 1.6 Source.rar" archive.
6.)Extract it, for example, to your Desktop.
7.)Open extracted "game" folder.
8.)You will see the file, called "csport.bat".
9.)Double left-click on it.
10.)Play.
