Up until October, Jeff Smith's software can be downloaded from: http://homepages.nildram.co.uk/~jasmith/download.htm

Click on the 'Download' link corresponding to the program that you wish to download. In later versions of Windows, this usually causes a installation file to be saved to your 'downloads' folder, but often with a button appearing at the bottom of your browser. You will need to open this file.

It is likely that your Windows security / anti-virus software will raise some concerns about downloading from an unknown source, but just keep on saying 'Yes' to any 'are you sure?'-type questions!

Eventually you will get the “Setup Wizard” which will ask you a few basic questions: I suggest that you accept the default options in all cases, with the possible exception of the “Destination Location”:

The default location will be “C:\PairsScorer” (or C:\TeamsScorer, etc.)
Personally I prefer install the programs in a dedicated folder for all the programs, e.g. “C:\JeffSmithScoring\PairsScorer”, “C:\JeffSmithScoring\TeamssScorer”, etc.