I need to set up an API key at http://developer.constantcontact.com to link all the email sign up to the constant contact account. When a customer signs up, the information will automatically go to Constant Contact email list for Lanafurniture.
Constant Contact API is a WebService API that allows you to connect almost any website, application or piece of software to Constant Contact. The answer to your question really depends a lot on the technology you're building your website on and the web form you're trying to integrate. Regardless of the technology, to do this you will need an expertise in web development and web software programming. We have a variety of wrapper libraries and code samples that you can find here: http://community.constantcontact.com/t5/Documentation/Code-Samples/ba-p/25019
Dave Berard Senior Product Manager, Constant Contact