Check username using ntier architecture

Hi Friends,

I have login page and once user enter email id and password, I am assigning this values to BO Layer class file (UserBO.vb).

Now Problem is

I need to fetch this assinged email id in the default2.aspx from UserBO.vb
I have tried
Dim UserLogin As New UserBO

Because of New Keyword UserLogin is empty and If I remove New Keyword then getting error as

Object reference not set to an instance of an object
Need Help!! 

Th ...