Login system Help

Hello there.:)

I have developed a static website using expression web 2.
You can visit it: Getpak Website (http://www.getpak.com.pk)

Now i want to add a login system. but i found that i can use aspx controls in expression web but cant add my own c# code. hope you got my point.
can anyone give me suggestion how to do that.

if i make a asp.net project in visual studio and then can i merge it with my expression web website?
another option will be using PHP? but i dont want to:(


Is there any other working way? site is pure html so how can i add login register system.

thanx

Don't know which version of ASP.NET you are using.

Here's a walkthrough for ASP.NET 4 on creating Basic User Login page(s)
http://msdn.microsoft.com/en-us/library/ff184050.aspx