I recently went to the new quickbooks online. How do I create a billing statement of open items to send to my customers like I used to do easily before?

From the Homepage screen

      Click “+” sign (top middle)
      Select “Statement” under Other header
Statement
Statement

How to email statement to a customer?

      Select “Edit” under Delivery Method column
      Default could be “None” 
      Select “Email” from the pop up screen and follow the instructions
      Select “Create/Send Selected Statements” button
      It will send email and will end with “Statements Created” message report.
Statement Delivery Method
Statement Delivery Method
Statement Choose Type
Statement Choose Type
Statement Delivery Email
Statement Delivery Email
Statement Created
Statement Created