Click on the API Services option under the My Account Section.
All the created API Services of yours will be displayed on your screen regardless of whether they are Active or not (Green header = active API Service, Red header = inactive API Service).
Apart from being able to view a list of your API Services, each Service's details are also available so that you can always refer to its parameters.
You can also get an overview of:
Created: The date you have created the subject API Service
API Key: Your unique API Key for the subject Service
Note: The displayed parameters and information may vary depending on the API Service.