Hi Celeste, thanks for the feedback. At the moment the site generates notifications when there's activity on a post or thread where you've participated (and as you noticed, that includes your contributions! :). I agree you don't need to be notified of your own activity and we'll check how easy or difficult it is to turn that off.
In the meanwhile, if you want to, you can turn off the notification for each activity subscription that the site generates. There's a good description (with screengrabs) in the user instructions on the help page (see page 14), so that would be the best place to look. But in summary, just go to view profile > edit > subscriptions. Click on the 'manage' link next to the one you want to change and on the next screen you can make it temporarily inactive or unsubscribe all together.
If you don't want to receive notifications at all, you can do that on the edit > password & subscriptions page (there's a good explanation for that in the user guide, too), but that means you won't get any notifications at all.
Regarding the conference, you're most welcome to join the group. If you'd like more info on the Conference itself, then the conference info page is here: http://www.ywcaustralia.org.au/index.php?option=com_content&view=article&id=17&Itemid=23.
Hope that helps, but let me know if you need anything else.