The description given implies to me that you want to net the debt holdings between governments only. For example, we would subtract the Chinese government's holdings of U.S. Treasury securities from Chinese debt (and so forth).
I am unaware of any such statistics. For the developed countries, the amount of cross-governmental debt holdings is minimal (excluding the ambiguous situation of the European Central Bank). Therefore, such an adjustment would only matter for some developed countries. (The ratio of governmental debt to reserves - which are holdings of developed country debt - is probably looked at by ratings agencies and analysts of developing countries.)
A more usual statistic is the net international position, which compares national holdings of foreign assets versus foreign holding of domestic assets. However, this mixes all form of financial assets (debt and equity) and includes both the private sector. The IMF has a standard for reporting the international investment position - link to page
The usefulness of such statistics enters the realm of opinion. The main usage of the net international position seems to be the assessment of the odds of a currency crisis; I am unaware of the literature on that subject.
As for debt statistics, things like the debt-to-GDP ratio have been greatly discussed. However, I am in the camp that argues that the main "use" of debt statistics has been to generate incorrect forecasts (such as the sustainability of Japanese debt). In general, the link between debt levels and bond yields for the developed countries is questionable, which indicates that bond investors are not greatly impressed by the importance of debt statistics.