The ssh home page is at http://www.cs.hut.fi/ssh/.
The Unix version of the software is mirrored throughout the world, and it originates from ftp://ftp.cs.hut.fi/pub/ssh/.
Commercial implementations of the package are distributed by DataFellows: http://www.datafellows.com/.
The designer of ssh has founded his own company, whose entry point is http://www.ssh.fi/.
The ssh faq is at http://www.uni-karlsruhe.de/~ig25/ssh-faq/.
As far as cryptography is concerned, a good starting point for net surfing is http://www.cs.hut.fi/crypto/.
The IETF is at http://www.ietf.org/, and the group dealing with ssh standardization is at http://www.ietf.org/html.charters/secsh-charter.html.