Prices on campsites, Caravan Parks.... ?

In Wikicamps people can enter what they paid. However with "dynamic" or seasonal pricing that may not be what it is when you want to book.
Exception may be Government owned facilities such as NP which I've observed have the same pricing year around.
If I was the owner of such a website, I wouldn't want the responsibility of keeping ul to date with camp ground fees through the year.

Mark, I think many caravan parks change their rates seasonly and would find it too much trouble to have to keep readjusting their websites to suit.

EDIT: Sorry Mark (Tamworth), I didn’t see your reply before responding.

When on the road, WikiCamps is your best friend.

Just like Wikicamps, ExplorOz Traveller app users can enter prices - we don't separate where to put it, just put it in the Review section which enables you to see the time stamp of the comment and make up your own mind if that is recent enough, or if you want to give them a call or view the website - links to both should generally be visible. The whole app content is fully user updatable - doesn't require admin to enter pricing, or links, or phone numbers, or descriptions but we do as we travel, and we do get lots of user generated updates and have a small little team of busy bee volunteer helpers entering updates but could just be the sites you're looking at - so if you find out, enter them.
Cheers, Michelle