I have checked http://www.lfd.uci.edu/~gohlke/pythonlibs/, http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//003m00000002000000.htm, and https://pypi.python.org/pypi/pygeoif/0.4.1
None of these logical places can I download arcpy for installation. I have also tried Pip install arcpy. Nothing works.
ArcPy is part of ArcGIS, which is not free software. You need to obtain a license for ArcGIS to use ArcPy.
If that's not an option, consider open source options, such as GDAL and many others.