If you are in need of an API key, the best way to get one is to follow steps 1 and 2 here. If you're having any difficulty getting your API key or after you have your key, please let me know!
To give some advice specific to the URL in case that is the issue, we require a URL to begin with http:// or https:// when registering an API key. As an example, www.google.com becomes http://www.google.com
Elijah G. API Support Engineer
View API documentation, code samples, get your API key.