Ken, the easiest way to find if any category already exists, is to use the category picker tool in edit mode on a profile. That's the icon second from the right in the row of icons above the edit box. Clicking on that brings up a box, start typing, say John Mitchell, and any available options come up. I usually type say, John Mit arrr, narrows the choices to our ships, but you can use it to find any categories, location and so on. If the one you want comes up, choose it and it adds to the profile.
I maintain the best page to bookmark is Australia Project Resources, one of the tabs on our Project page, but the go-to page for everything Project and Australia related. You'll find the link to the request page, plus links to lots of other Australian parts of WT. Let me know if there is something you cannot find from that page.
As always, you're more than welcome to PM me anytime, I added this info as a comment, as it might be useful to others as well.