Hi Barbara, nice to meet you! :)
One of the best ways to meet other members is to make a post in your own blog which will then show up on the All posts page (you can see that here, if you haven't already found it: http://www.bcna.org.au/node/all/blog/network). This is a quite old post, so people might not find your comment.
To make a blog post, just click on the 'my blog' link in your pink profile box on the right-hand side of the page. When you get to your blog section, you'll see a 'create a post' link up near the top of the page so just click on that and fill in the posting form, then scroll down and click submit. You can post about whatever you like (just remember the online network is public, so only post things you feel comfortable sharing).
To find an online interest group, go to the Groups search page and search on whatever your interests are: http://www.bcna.org.au/og/all) . When you find a group you're interested in, click on the group name, which will take you to the group homepage, and you'll see a 'join' link on the left side under the userpicture.
Or, if you're looking for a face-to-face group, you can find one in your area by searching the Member Groups section: http://www.bcna.org.au/membergroup/search.
Hope that helps (it's a lot of information!), but just ask if you need a hand. Welcome again, and I hope you make some good contacts here. :)
Di