Windows API Tutorials? or Function reference

Im looking for help there, i''d like to find a reference to all the Windows API function particularly stuff having to do with Arguments ie:

void Arguments(char bla, ...)
{
  va_list args;
  va_start(args, bla);
  // Stuff
  va_end(args);
}
 

cause i quiet understand what it do but i''d like to be sure. "The bible is probably the most genocidal book ever written!" Noam Chomsky