I've had a client up and running on SBS 2003 Standard for about a year now.  I use the following sites as reasources:

E-Bitz - SBS MVP the Official Blog of the SBS "Diva"

Inside SBS

SeanDaniel.com on SBS 2003 & other Tech-stuff

but the first place you should start is:

SmallBizServer

Lots of good tips, tuturials and best practices.  As far as tips from me, it all depends on what the server is used for.  You're not using Exchange so that eliminates some headaches there.  Are you running Premium or Standard?  What's the servers role?