The Create Geostatistical Layer tool takes a model source as input. This model source can be a geostatistical layer (either a layer in ArcMap or saved as a .lyr file on disk) or an XML model source. For your purposes, the XML will be easier to use. The tool reads all the interpolation parameters from the model source (type of kriging, nugget, range, sill, transformations, etc) and applies them to a new dataset. This is useful for something like temperature data taken daily. You can build the model for one day and easily apply that model to each subsequent day.
However, if you're using different kinds of data (temperature, elevation, pollution, etc), you don't want to keep using the same model over and over because the interpolation parameters will not fit different types of data. So, you need to tell the tool to recalculate all these parameters (explained below) for each new dataset.
You only need to manually create one XML file source. You can do this with the Geostatistical Wizard. Open the Wizard, choose Ordinary kriging, and give it a dataset. When you click Finish, the Method Report screen will pop up that shows all the parameters that you used. Click "Save..." and save the XML file in a convenient location. You then need to open the XML file with a text editor (Cooktop is a useful and free XML editor, but you can do it with Notepad too). Inside the XML, you'll see all of the parameters, and most of them will have auto = "false" after them. This auto flag tells the tool whether to recalculate that parameter or keep it fixed when it is used as a model source. For every parameter that you want to be recalculated, you need to change the flag to auto = "true" and save the XML. You only need to do this once, and you'll keep reusing this same model source.
You can then set up a loop in Python to iterate through your datasets. For each dataset, you'll use the XML as the model source in Create Geostatistical Layer. This will generate a geostatistical layer for each dataset, where the interpolation parameters have been recalculated, and you can use these layers to create the ASCII files that you described in your first post.
The difficulty in automating Ordinary/Simple kriging is one of the many reasons we made Empirical Bayesian Kriging as a geoprocessing tool.