I have done this about 5 different ways, and it depends what the customer wants.
As standard you can press email and it will attach the print out as HTML to the defaul mail client with no email address.
Consider the formatting of the report, preference is to use PDF.
Consider which email address to use, new fields, the default email, the default contact, the contact flaffed as PO Receiver. Then modify an email report to pick up the relevant details and launch the default client. Then you have the consideration of what to do if they want batch printing.