ISU explanations are sometimes better than USFSA explanations. Most of us aren't good enough to compete internationally - but since ISU regulations regarding skating largely trump national club regulations in International competitions, national clubs like USFSA often adapt most of their standards, but with less explanation and much poorer documentation.
I think the ISU rulebook equivalent is visible by clicking on the "Extranet" tab at http://www.isu.org
However - now you have to login.
So, to the extent that ISU rules affect USFSA and other national skating org rules, perhaps you have to become an ISU member to see them in full?
But some of the rules are visible from the "About ISU" tab, e.g.: http://www.isu.org/en/about-isu/isu-statues-constitution-and-regulations
Of course, like USFSA, the rules are frequently updated through technical rules changes. I'm not sure where those are posted.
And the ISU sells some things: http://www.isu.org/en/about-isu/publications-for-sale