You've basically got it. Weeble does not exist. You'll find those pages are just the FogBugz pages, with the word "FogBugz" replaced with "Weeble" by search-and-replace; it's from our website template. Google picked up on a link that was given display: none instead of removed, so Google indexed them anyway.
In answer to your questions:
Kiln is a separate product from FogBugz, although Kiln requires FogBugz.
Kiln pricing has not been finalized. Kiln will be free throughout the beta, which is currently ongoing.
Weeble isn't a real product, and has nothing to do with Kiln.
We'll get the dud pages removed as quickly as possible.