IIS is Internet Information Server. It's your web server. If you're your
own "host" for this web site then you should be familiar with IIS, how it
works and how to configure your web site. If not you're running a HUGE
security risk because the chances that your server is wide open for attack
are very possible. You should really look into some books on IIS if you're
going to host your own site(s).
To find it go to Control Panel, Administrative Tools, Internet Information
Server. If you're running Windows 2003 Server (or 2000 Server) then it
should be in your Start, Programs menu