Ryoko - depends on your needs from the ISP, and budget. Also area where you are, and speed you would like.
TalkTalk now owns Tiscali and Pipex plus AOL, Freedom2Surf and perhaps others, not sure how many BT may have bought, but I know PlusNet (while owned by BT) is run independently and also runs Madasafish, Force9, and Metronet (I've been with them off and on for 5+ years and their overnight unlimited downloads from 00:00-08:00 are very handy, available even on the lowest cost a/c at about 7 quid, which has a 10 GB limit 08:00-00:00, and can be set to go slow if you exceed the 10 GB or you pay a fiver extra [but note the extra 5 GB allowed does not carry over to next month, so I advice people against it].
Then there is Eclipse in Exeter (owned by Kingston Communications in Hull), Zen (not cheap), AAISP (not cheap), and there are others such as Demon offering access at up to 20 Mbps if your exchange has Cable + Wireless kit (previously used for Bulldog) but Demon has a 2 year contract (long!). Also consider O2/Be Broadband (use own kit so not across whole of UK)
Other firms like UKFSN have been Enta.Net resellers but now seem to have moved to some other firm (C+W I think), and then check out Vivacity, Xilo, ADSL24, Aquiss. Sorry, not fully up on pricing from these other ISPs. I pay under 12 quid and get 60 GB allowance which suits my daytime needs, and then maybe 100 GB off peak on top, depending on how much BBC iPlayer downloading I do.