I'm here to lend a helping hand in finding the consumer key to integrate with your website. Let me get you pointed in the right direction.
There's a community dedicated to developers and integrating other websites with QuickBooks. I recommend that you sign up and post this question to our separate online forum called Intuit Developer Community.
This site contains resources for software development, as well as the ability to ask fellow developers questions. Our Intuit Developer can provide the consumer key you need to integrate Intuit Payments into your website.
You can find additional information about this at the following link: Intuit Developer.