Checkout the Microsoft Dynamics GP 2013 Readiness Training and Resources from GPUG.
Microsoft Dynamics GP 2013 Readiness Training and Resources – GPUG Events & News – GP Non-Technical Blogs – Microsoft Dynamics Community
Microsoft & the GP EcosystemGP 2013
Archived post from 2012. Dynamics GP and the links it points to have changed since; check current documentation before relying on version-specific steps.