Fastcube

Fastcube is an SAS-IML macro that allows selecting balanced or stratified balanced samples by means of the cube method.
download

R'sampling package

The R sampling package is a package in R language that contains a set of tools to select and to calibrate samples.
Download the R 'sampling package' and its manual

http://cran.r-project.org/web/packages/sampling/index.html

Download the R language
http://cran.r-project.org/