You can learn more about responsive design from udemy below:
http://goo.gl/keOUMv
This is a tutorial where I go over how to make a responsive emailer for marketing uses. This email is responsive. I go over how to create a call to action button, autoprefixing, and what css codes make the webpage responsive.
Plus I talk about what images are legal to use. This is advanced tutorial where you would have knowlege of css, html, sublimetext, and emmet. I'm expecting you to have knowledge of HTML5 div classes and css styles.
Web tools used:
http://templates.mailchimp.com/resour...
http://placehold.it/350x150 for placeholder images