Automatic Invoice Software

As a private tutor, I enter my monthly schedule into an excel spreadsheet. I need a piece of software written to perform the following tasks: 1. I select the month and customer (or all customers), push "go" and the software should then generate separate pdf invoices based on the information held in the spreadsheet. These pdf files will be saved in a folder of my choice. 2. I select the month and customer (or all customers), select either a preconfigured email or write a custom one, push "go" and the software should email the pdf invoices to the appropriate customer using my gmail account. Please note that multiple users will need to be able to use this software and will each have different excel spreadsheets and different gmail accounts. They should be able to select the appropriate spreadsheet on first use and have that data stored so that they don't need to select it every time. I have added a sample excel spreadsheet and sample invoice file.