Cal,
Regrettably, you are correct. Corel's "powers that be" were apparently disappointed by the sales of the Paradox 9 Developer's Edition and chose to stop selling Paradox as a separate SKU (product).
Currently, the only way to obtain Paradox through common retail channels is to upgrade to the Professional Edition of WordPerfect Office 2002. Fortunately, the upgrade includes Paradox Runtime. So, unless you really need nine copies of the Developer's Edition, you should be able to get away with upgrading to one copy WPO 2002/Pro and the using the Runtime to redistribute your Paradox applications.
If you already have a copy of Paradox 9 Developer's edition, there's an interesting caveat to Corel's license agreement. They'll let you happily reinstall that one copy to other machines *provided* you have a valid license of the same version or a later version. This includes WPO 2002/Pro. It's a little odd, I'll admit, but it might also be a way of handling the versioning problem.
For example: I had a backup copy of Paradox 8 Runtime, but could not locate my original CD; however, because I also had a copy of Paradox 9 Dev. Ed., I was still "officially" licensed to use the Paradox 8 Runtime. Weird, eh?
Alternatively, you *might* be able to call Corel's sales line directly. I know that some vendors will continue to sell older versions directly after they've pulled them from the retail channel. (After all, someone's got to clean out the warehouse.

)
Finally, if worse comes to worse, you can always try one of the auction sites, like ebay. Use care, though, for it's very easy to get ripped off from them. I've used them to get replacement CD's for older versions (e.g. Paradox 8) and haven't had too many problems, but you have to verify that you're getting what you think you're getting before you bid.
Hope this helps...
-- Lance