Chaishop -
www.chaishop.com
These guys list Psy-Trance events throughout the world in a weekly mail out. If you want to know what's going on internationally, you won't go far wrong with them.
Psy-Trance Forum -
http://www.psy-trance.co.uk/
This is just about the fluffiest Psychedelic Trance forums around, covering all aspects of the scene from parties, to tunes, to production, to a very lively coffee shop general discussion area. I'm there most days :-). At the time of writing (July 2003) the web site itself is just about to go online.
Access All Areas - http://www.accessallareas.org/main.html
You've got to admire Amin and his team for all the hard work they do for parties, the people involved in them, and dance culture generally. The site is an amazing resource. Have a look and you'll see what I mean.