How can I create a web form in ASP whereby one user messages another?

I want one user to enter message in a text field, submit and for the message to appear in another users 'inbox', displayed on a webpage, not to their email account. (Although an email notification should also be sent)How can I create a web form in ASP whereby one user messages another?
Store the messages in a database and let user retrieve their messages by loggin ID. To send a notification, you need to use ASPMail script.