Google Maps - API 3.1 - How to set API key

Google Maps - API 3.1 - How to set API key

  
I’m in the Personal Environment
When I try the sample application, I receive an error message that states Google has disabled this key. Can I apply for my own API key?   I found the area in Google that I request and get an API key.  I did this in my person Gmail login.
 
How do I apply my own API key in my application or environment?