i need opengl1.2 for windows(*.h *.lib *.dll).where can i get it??
There is not, to the best of my knowledge, any such thing as a 1.2 version of the .lib or .dll.
The drivers (most of which are up to 1.4 now) link to the 1.1 version which is standard with Windows (ie. the MS version) and the drivers switch to the specific vendor version at run time. To use the 1.2/3/4 functionality you need to research the user of extensions and use wglGetProcAddress() (or the Linux equivalent).
As for the .h - the latest version is available on this site somewhere (I’m too lazy to find it for you) and/or through the GL SDK available from your cards vendor.