Microsoft offers up a new GP 2013 Feature of the Day: Use Multiple Budgets with Encumbrance Management
Feature of the Day: Use Multiple Budgets with Encumbrance Management – Inside Microsoft Dynamics GP – Site Home – MSDN Blogs
General Ledger & FinancialsTips & Hidden FeaturesMicrosoft & 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.