I recently had to build a SVNserver for a client and needed to setup the command to start of the SVNserve on the Mac OS X 10.5 machine. I wanted the documents to be stored on the server in the admin account. Here are the commands for future reference.
Start up SVNserve on Mac OS X with a custom folder
svnserve -d -r /usr/local/repositories
SVN create new project
svnadmin create PROJECTNAME
Just used this to create a new project. Enjoy