Is there any good reference book / material available online for Cisco MARS. I'm pretty new to it and looking forward for some basic and conceptual knowledge.
Start with the User Guides like Matthew suggested and then do the following.
1. Visit the following blog:
2. Visit the following Web site to view the MARS demos:
Finally buy this book from the Cisco Press by Dale Tesch, "Security Threat Mitigation and Response."
You should also keep an eye out for another MARS book that is due in June:
Security Monitoring with Cisco Security MARS (Networking Technology: Security) (Hardcover)
by Gary Halleen and Greg Kellogg
Hope this helps.