The first stable version of Joomla 1.5 is available for download at

Now that Joomla 1.5 Stable is available you might be looking for a manual and some tutorial videos.

From the official Joomla site:

Joomla 1.0.13
"This release features several improvements to the password storage system designed to help protect the future security of your Joomla! powered website.  These changes will cause compatibility issues

SSL Secure Connection