Hi sjaakmans - Sme server is really great!
It does come with a user webspace tool called ibays - check 'em out in the user manual.
It also works with yum - sort of an rpm-based apt-get. Yum is built in to SME 7 (which is coming along nicely, thanks to the great developers) or you can add it into SME6.x. Look around the site, or search for "yum" for more info.
Welcome, and Good Luck!
RonM