Web Forms :: Programmatically Implement A Facebook Style Page Access?

I have an asp.net app that allows users to create personal pages which can be publicly accessed thru a "directory" page. The content of the pages is stored in sql server, so a given user's page is dynamically created thru the code that executes when the relevant link on the directory page is clicked.

I would like to take this a step further by allowing access to a given user's page directly thru the browser's address bar, something like www.thegreatestsite.com/jim (pretty much like You Tube, Facebook, etc.).

I could achieve this by manually creating a folder under the root, called "jim" and putting a default.aspx page in it which would have code in it's load event that would dynamically create jim's page.

However, I would like this "additional feature" to be created automatically, as part of the sign up process of the user.