Creating an Http API for AWS Seller API

I'm working with a C# MVC project which will require data from the Amazon store. I've created an account so that I can use the AWS Product Seller API to request JSON data from the various API's. I've worked with REST API's many times so having gone through more documentation than I've ever seen in my life I felt confident I could find what I needed to create the correct API. However, there seems to be many tools and wizards for users but I've struggled to find anything that just said 'Using Http://AmazonAPI.com just use these parameters to get the data you require'.
I've no doubt that there are many here that have successfully done this so I would appreciate a heads up on what URL I need and where I add my security tokens, access id and details of my request.