Time to time OSA::net releases some files. Although software is in alpha phase, these releases contain some finished functionality and are considered stable. You can gather them at sourceforge download area.
If you are willing to live on bleeding edge, you may grab CVS sources. Again there are two possibilities. You may either perform CVS checkout:
cvs -d:pserver:anonymous@cvs.sourceforge.net/cvsroot\
/osa-net checkout osa
