Using Email address as Username in Asp.net Identity with Webforms

Hi All,
I spent hours in searching for good and clear documentation about how to implement a simple registration form with asp.net identity withWebforms to allow users to use only their email addresses to register their accounts (instead of usernames, being the default configuration).
So far no luck. I see plenty of MVC documentations which I don't really need.
My aim is apparently simple but it's giving me some headaches:
1) creating a registration form which allows users to register only using their email addresses
2) creating a verification email to unblock their accounts once the verification link is being clicked
Can you possibly share some code or driving me to an effective documentation?
Thank you