I also recently made my cross compiler for i586 architecture for use with an operating system
Basically, i've just followed this guide : http://cowlark.com/2009-07-04-building-gcc/
Note that you might have some missing dependencies that you should install first
The guide though assumes you to be using linux to build the cross compiler.
I also use the BeagleBone Black a lot. Linaro is my favorite tool chain, and is available for linux and windows. Al my applications are written on a windows 8 machine in Eclipse, compiled with Linaro an send to the beaglebone by Eclipse.
When u use Linaro, u need to download the make executable seperatly since this is for same resone not included with Linaro.