Sadly you will find that if you didn't grab these while they were available it may be that Microsoft has removed them from the web sites.
Some rail against this but Microsoft and other companies license content, apps and such and when the license expires they can't offer them anymore. Witness those older HP printer drivers that you can't find anymore.
Since you are a programmer, author and more, is it time to consider other solutions? Let me find one.
http://cmusphinx.sourceforge.net/
That one is interesting since it's in Java and therefore not tied to the OS.
Bob
I have Windows XP but Microsoft Office 2000 Professional. I really want to get Speech recognition from Microsoft(I am making voice command software and I need the microsoft version). I have tried installing it from "Add Remove Programs" but I have no program in the list called Microsoft Office XP, and when I choose MIcrosoft 2000 it doesn't show an update for Speech Recognition. I even tried to use a free trial of Microsoft Office 2010 but I couldn't figure out how to get Speech Recognition from there either. I have celeron D intel. If you have any questions ask, and please give me any ideas on how to get speech recognition. I also tried the 5.1 Pack from Microsoft but couldn't get the files to work.
Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic