I can't find a list of ISPs owned or controlled by Tiscali but you might find some helpful info in the links below.

::. Kitz - ISP Caps, FUPs and Throttling .::

Tiscali - Wikipedia, the free encyclopedia

Tiscali executes stealth LLU migrations - The Scream!

Tiscali UK To Conclude Broadband ISP Sale in March 2009 : ISPreview UK News