Books PO Due Date on Calendar

Books PO Due Date on Calendar

Hello, I am currently looking for a way to add calendar events to either an Exchange or Google calendar to track PO's based on their estimated due date.  Does anyone know how to write a function that would be able to do that?  I know we have done it in CRM, but this would be in Books instead.

We want something as an all day event, with the PO# and Vender in the subject line.