Hi
To add the reference of your web service to your application, you will have to first host it, you when you host it will be accessible with localhost url, otherwise while development it opens up one port of it, so you can add the reference of that url also locally, but if the port is changed it will not work, so do the following
1) If its ASMX just host it in IIS, create virtual directory, and select the folder where you WS is, and give anonymous user rights, so that now if you can browse this web service, just copy that url and than try to add reference in your application, that will do
let me know
Thanks