I have used the createUserwizard, customized it and add a couple of more fields.
Protected Sub CreateUserWizard1_CreatedUser(ByVal sender As Object, ByVal e As EventArgs) Handles CreateUserWizard1.CreatedUser
Dim UserNameTextBox As TextBox = CType(CreateUserWizardStep1.ContentTemplateContainer.FindControl("UserName"), TextBox)
Dim DataSource As New SqlDataSource
DataSource = CType(CreateUserWizardStep1.ContentTemplateContainer.FindControl("InsertExtraInfo"), SqlDataSource)
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