How do I integrate a unsubscribe link on a web page to my Marketo list

Lars - you want to be careful here, you don't want to encourage unsubs any more than you have to. While you do want to follow compliance standards, you will be better off getting your users to tell you what they want or perhaps don't want any longer, but you will have diminishing returns if you accelerate the unsub process.

That being said, you can always use the URL of the unsub page found in the administration section under email settings.

Thank You for your answer, Clinton. 

You are right! I don't want to encourage any unsubs. 
I will figure something out. :)

Thanks