Microsoft is running a set of blog posts around year end. Checkout the Microsoft Dynamics GP Year-End Closing Blog Series 2012 Schedule for more.
Microsoft Dynamics GP Year-End Closing Blog Series 2012 Schedule
Year-End & 1099Microsoft & the GP Ecosystem
Archived post from 2012. Dynamics GP and the links it points to have changed since; check current documentation before relying on version-specific steps.