Go through this video to have initial understanding of products stated in subject. Forefront team, PM is explaining about them at http://edge.technet.com/Media/FPE-vs-FOPE-and-Exchange-2010–Secure-messaging-with-Forefront/
FPE RC for Exchange 2010 is available for download at http://www.microsoft.com/downloads/details.aspx?FamilyID=b8a7d36f-cc8d-4335-ae60-8f27c48f3a37&displaylang=en#filelist
Happy Learning,
Sitaram Pamarthi