Help me add a call to action to my blog on wordress -- 2

I am looking add a call to action form to my blogs on Wordpress similar to what this site did: [login to view URL] Please note how you scroll down the page, the form continues to scroll down. I'd like the form to have that effect. Also, I am not looking for a clone of this form, just something similar. My objection is to capture client Name, Email, and Phone number. My Website is [login to view URL] Please let me know what you can do.