I will show you how to setup NetBeans to create 64-bit C/C++ Windows executables with NetBeans 7.4. This will also allow you to create and compile 64-bit GNU Assembly (GAS) programs. The first thing you need to do if install Oracle JDK and NetBeans 7.4. I will not go over this as it is clearly documented.
Next you will need to download C/C++ build tools for NetBeans to use. You can either download Cygwin or MinGW build tools, but I prefer MinGW because it is lightweight and far more easier to install. There are two websites for obtaining MinGW. One is the old website http://www.mingw.org which leads to it's SourceForge project page for downloading the older 32-bit only installation and the other website is http://mingw-w64.sourceforge.net where you can install MinGW-w64, which is the 32-bit & 64-bit installation.