Hi gime , and welcome to vl.
We have a tool called slapt-get , that is, obviously, the equivalent to debian's apt-get
slapt-get --install foo
the equivalent to sources.list is /etc/slapt-get/slapt-getrc (IIRC, not @ my vl machine now)
gslapt is the graphical front-end to slapt-get (hey synaptic!).
Btw, you won't find as many packages as in debian. Our repos are growing day by day, but being a small community, it's impossible to catch up bigger and economically supported distros (at least in packaging matters).
We have some tutorials about packaging apps for vectorlinux too. Make repos grow is a community job here