To set the default location of an outlook data file you have to make a registry change. Once you make the change, anytime you create a new data file, Outlook will put the data file in that new location.
Read more at source: http://blogs.technet.com/b/danstolts/archive/2012/11/07/how_2d00_to_2d00_change_2d00_default_2d00_data_2d00_file_2d00_ost_2d00_location_2d00_in_2d00_office_2d00_2013.aspx
Cheers,
Anderson Patricio
http://blogs.msexchange.org/patricio
http://www.andersonpatricio.ca
Twitter: @apatricio