First of all, to get a readable overview of any of our VCSes:
http://vcs.openttd.org/svn/
http://vcs.openttd.org/git/
http://vcs.openttd.org/hg/
Or, their https alternatives:
https://secure.openttd.org/vcs/svn/
https://secure.openttd.org/vcs/git/
https://secure.openttd.org/vcs/hg/
The place to get your checkout from has changed to.
For SVN is now valid:
svn://svn.openttd.org/
http://svn.openttd.org/
https://secure.openttd.org/svn/
For hg (mercurial):
http://hg.openttd.org/
https://secure.openttd.org/hg/
For git:
git://git.openttd.org/
http://git.openttd.org/
https://secure.openttd.org/git/
As you can see, enough places to pick from


Any questions, please ask!