Stefan Stranger wrote extremely good and useful article about Monitoring non-domain members with SCOM 2012. The article can be used for SCOM 2007 R2 as well. Click on the link and read.
Monitoring Workgroup server with SCOM 2012
Stanislav Zhelyazkov
Article, Microsoft, Software, System Center, System Center Operations Manager, Windows
1 Minute
Published by Stanislav Zhelyazkov
Stanislav Zhelyazkov has been working in IT since 2007. Stanislav has started his IT career as a Help Desk Specialist in 2007 while studying Informatics in the University of Ruse. He also worked in HP Enterprise Services (now known as DXC), maintaining large corporate IT infrastructures for clients in Holland, Switzerland and Germany and was involved in a Private Cloud project based on MS Hyper-V and System Center. He was also in the role of Principal Consultant in Lumagate developing and consulting companies on Azure, OMS, management and Private clouds. Currently he is Cloud Infrastructure Engineer at Sentia Denmark. Stanislav is active community member at MSDN forums providing answers on Azure. His blogposts can be found at www.cloudadministrator.net or www.systemcentercentral.com. View all posts by Stanislav Zhelyazkov
Published
Cloud Administrator in Azure World 
Lovely just what I was looking for. Thanks to the author for taking his clock time on this one.