There are two tracks of certifications in MS Dynamics GP
1. Microsoft Certified Technology Specialist (MCTS)
2. Microsoft Certified IT Professional (MCIP)
MCTS goes into every module of GP, so normally people start with MCIP.
There are two exams in MCIP for GP.
• Applications for Microsoft Dynamics GP 10.0
• Installation and Configuration for Microsoft Dynamics GP 10.0
The recommended one for starters is the second - Installation and Configuration.
These links might help: http://www.microsoft.com/learning/en/us/exam.aspx?ID=MB3-527&locale=en-us#tab1
All the best!