To create a new project, you can simply check out the repository root
and create your project next to the sample project, with a trunk
folder inside it. Do SVN Add followed by Commit. Then add your code
inside the new trunk folder.
If you don't want to check out the root folder (it is impractical when
your repository gets bigger), you can use svn import. See
http://svnbook.red-bean.com/nightly/en/svn-book.html#svn.tour.importing
and
http://tortoisesvn.net/docs/release/TortoiseSVN_en/tsvn-dug-import.html
Good luck with your new server. Subversion is really a great tool.
/Staffan