It's part of Windows normally.

Start > All Programs > Accessories > Communications.
Hyper terminal is quite sh*t though try and grab yaself Terra term i'm not sure if ive still got the exe file if i have i'll upload it for ya as its much more reliable.
My Hyper terminal has a tendency to crash and its quite widely reported or it was when all this modem cloning scene began, i just find it a pain in the arse having to reboot my modem every once in a while.
i dont mind hyperterminal like i dont use telnet mutch anyways just for me modems i use putty for ssh and that so like its cool for me ;)