Add the local server (I add a local mirror plus an Australian mirror at aarnet) and the US server to /etc/apt/sources.list:
deb http://datamining.csiro.au/pub/debian unstable main contrib non-free deb http://datamining.csiro.au/pub/debian unstable/non-US main contrib non-free deb ftp://mirror.aarnet.edu.au/pub/debian unstable main contrib non-free deb http://ftp.debian.org/debian unstable main contrib non-free deb http://non-US.debian.org/ unstable/non-US main contrib non-free deb http://security.debian.org/ stable/updates main contrib non-free