Are you looking to use the GD library out of PHP?
If not just enable the GD library in your extensions list
Download the complete PHP from PHP.net (the zip around 4M😎
In the PHP.ini make the following modifications
a. set the extensions path
extension_dir = c:/php/extensions/
b. Unrem ;extension=php_gd.dll
c. Change to read extension=php_gd2.dll