There are two practice tests available for the Configuring Groove exam 70-555 from two providers, one from Selftest engine and another (allegedly since it isn't yet listed in their catalog yet) from MeasureUp.  

A new collection of online courses is available. This material prepares people for Exam 70-555, Configuring Microsoft Office Groove 2007 Collection 6452: Implementing Microsoft® Office Groove® Server 2007 In this 12 hour on-line collection, IT Professionals will learn how to Implement, Configure and Manage Microsoft Office Groove 2007. ...

Microsoft Office Groove 2007 Fundamentals & Technical Training for Partners and IT Professionals Microsoft Partners are invited to attend Groove Fundamentals & Technical Training.  Participating in this training will help prepare you for taking and passing the Microsoft Certified Technical Specialist Exam 70-555: Configuring ...

Microsoft has a new collection of courses,Collection 6452: Implementing Microsoft® Office Groove® Server 2007 In this 12 hour on-line collection IT Professionals will learn how to implement, configure and manage Microsoft Office Groove 2007. Topics covered within these courses include: Installing and Deploying Microsoft Office Groove ...