.net Security Tools And Frameworks?

As per the increasing security threats, my site needs extreme care in terms of security in all aspects. I know asp.net has built in some security measures (Anti-forgery token, cross-site scripting, authentication, roles), but that is just not enough.I need a tool to test all possible security threats (Brute-force attacks, .... IP location, browser info ... )and a framework (open source is better) that handles all these concerns and let you build upon.

EDIT,So to narrow a bit, my primary concern is protecting the "login" page from all possible threats.