I've tried using proxies but that also doesn't work as others have used the same proxies to download so you have to wait hours to download from the same proxy.
It seems TalkTalk (along with BE/2-0, BT, Sky, VM, plusnet) have indeed blocked access to some/all filesharing sites as a free user, meaning everyone is now treated as a potential pervert...uuurggggghhh! I'm raising this with the OCEs on the Talktalk forum, let's see what they have to say.
http://beusergroup.co.uk/technotes/index.php?title=IWF