To become an Associate, go to the Amazon Associates main page for your locale. Note that one of the requirements for becoming an Associate is that you furnish the URL of your site. If your site is not yet public but you want to test against the API, you still need to supply a URL as part of registration.
When you register as an Amazon Associate, an Associate tag is sent to you by return email. An Associate tag, also known as an Associate ID, is an automatically generated unique identifier that you will need to make requests through the Product Advertising API. When you log in to the Amazon Associates website for your locale, the page that you are directed to includes a message that says "Signed in as" followed by your Associate tag.
You need security credentials to call the Product Advertising API, authenticate requests, and identify yourself as the sender of a request. Two types of credentials are available:
AWS security credentials (access key ID and secret access key)
IAM roles are not currently supported. You must use the root account credentials or certificates.
To generate and manage your credentials, go to the AWS Security Credentials Console.
After you have obtained your key pair, you can make calls to the Product Advertising API.