Build me a landing page with an opt in subscription form

Hi, I am trying to build my subscriber list. I will do this by providing free 'content' (documents) in return for people providing their contact details. So I need help creating a basic landing page with a built in 'sign up' form. Once people subscribe using the sign up form, I want to automatically send them a pdf document via email. I also want to add their details to my mailchimp database automatically. The landing page will use a sub domain of my existing web site. Please let me know if you have any questions. Thanks Tony