Does anyone know how to or know a website that show how to install an aftermarket tachnometer to a 2000 civic ex?

It's tachometer. And no.

Yea other than the minor mispelled, does anyone know how to do it?

not to be a dick, but there is this great little thing right next to the New Thread button that you clicked. If you type in the words "tachometer install", you get a few posts which have covered this already. Here, I did it for you http://www.automotiveforums.com/vbulletin/search.php?searchid=196696