PostgreSQL is at www.postgresql.org, and Python is at www.python.org. RPMs and Debian packages, as well as sou rce code, are available for both of these tools.

The iCalendar module for Python is available from www.mxm.dk/products/public/ical/downloads.

For more detailed information about working with dates and times in PostgreSQL, a FAQ written by Josh Berkus is at techdocs.postgresql.org/techdocs/faqdatesintervals.php.

The Psycopg database adapter for Python and PostgreSQL is at initd.org/projects/psycopg1.

You can download the latest build of the Mozilla calendar extension, or of the Sunbird standalone application, from www.mozilla.org/projects/calendar/download.html.

The RFC for iCalendar is available at www.ietf.org/rfc/rfc2445.txt.