Compiling blender plugins on OS X 10.5.6

How do I find the c/c++ programming utilities on OS X 10.5.6? I have made it to the end of “The Official Blender 2.3 Guide” after working through the entire book. I had no problem with the Python scripting section, but after typing in all the sample code in the plugins chapter, I can’t find my c and c++ compilers. I’m stuck!

Are there any good open source c/c++ API’s out there for OS X?

Please help me.