Quickbooks 2012 has a new calender facility. Shown on the Icon bar and under the Company on the main home screen. You can add To do tasks and allocate them to specific customers and suppliers. The Calender will show the tasks that are due or indeed overdue.
It is a welcome addition to the new version of Quickbooks.
Intuit help video on new calendar feature. Copyright Intuit.
I'm a Qualified Accountant A.F.A, that has dealt with many SME's ( Small and Medium sized Enterprises) over the years, in all aspects of Accounting, Business advice etc.