what is uninstall procedure for software installed via "make install" on CentOS 6.2

Go into the directory that the source file was in and type make uninstall if that does not work then then there may be no directions for the uninstall. In which case you will have to do it by hand which you can do by redoing the make install and watching for what it installs so you can remove those. otherwise if you know the directory where your program is installed you can remove that. Something you should always do when installing from source is to use checkinstall

What does checkinstall do?

It makes the installation and thus uninstallation much easier by using your systems package management system. It will be able to automatically generate an RPM or YUM package that can be uninstalled later by calling for example yum uninstall httpd