In order to create snazzy social networking buttons, you need a link for the buttons to go to.
In the case of social networks like Facebook, make sure that you link to a public page and not a secure page within your account (because it wont work).
Log out of your social network before grabbing the URL to make sure you copy the correct one.
Navigate to the page you want to link to in your browser. Once you are on the page that you want to link to, highlight the address in your address bar and copy it.
Now you can paste your URL in the NiftyButtons button maker.