Cisco Call Manager Implementation Guide
You can have a flick through the Cisco Call Manager Implementation Guide and contact me on Twitter if you have any questions about it.
The above I found it very useful when studying not only for Cisco CCNA but in my day to day work as a Cisco SysAdmin for a very large company. Call Manager is great, overly complex to keep millions of people in jobs and entirely unnecessary for today’s VOIP led infrastructure but it’s certainly worth a read if you’re managing any kind of Cisco real-estate.
Also, don’t forget to check out www.cisco.com for everything you need to know about Cisco.