HI Rahul ,
Mostly person get confused they dont knw what they are looking for so it should be clr that
what are u using either linux or window if you are using window you can find my.ini that is the same file like my.cnf nd u can find it in the root . Or you can go for full path
wamp\bin\mysql\mysql5.5.16\my.ini
hope will be useful for you
Best of luck....!!!!