Hi,
I made a short "tutorial" of sorts about performance profiling using cocos2d's CCProfiler and CCProfilingTimer. It also includes slight tweaks to the source code to simplify using CCProfiler and CCProfilingTimer. Head over to
Using CCProfiler and CCProfilingTimer | fiftysixtysoftware.com/blog and download the zip there, it includes the modified source code files. Then just follow the instructions and you're set to start profiling. I hope this will be useful for you, and if you have any questions or suggestions how to improve, just let me know.