oExcel = CREATEOBJECT('Excel.Application') will create an Excel object, but how to I find out the possible command to use with that object.

I have seen a few, but I how do I find a list of all or some type of documentation.

For example
oExcel.Workbooks.Add
oExcel.ActiveSheet.RANGE('A1').SELECT
oExcel.ActiveSheet.Paste()
oExcel.visible = .T.

How do I insert a new top row into an existing XLS and populate one cell of that new row?