to get the API key you need to set up YOUR OWN developer key in facebook at this link. http://www.facebook.com/developers/apps.php
you click on set up new application and after you enter the app name (choose anything) it will generate the key.
To get the page ID number just go to the page you want to link it to and take the last string of digits from the url in the address bar.
highly recommend this app and a good webpage by developer