Several Cisco NetPro postings deal with FreeRADIUS configuration issues as well.
All the different wireless security options are covered in the FreeRADIUS HOWTOs
FreeRADIUS is certainly a viable option for a budget restricted work place with good open source engineers. Sometimes the cost of Cisco's ACS can stall the deployment of a project, or hold back the roll out of a secure wireless network simply due to budget constraints.
Someday I'll be at a point where I can stop & learn how to use open source software to complement existing Cisco deployments. I still have two Perl books that I never had time to dive into - the project deadline didn't allot enough time to learn a new way to configure a bunch of autonomous APs quicker than I could do it with telnet & notepad.