Searching the NET is the best answer but be aware of download limits and posted speeds. Why pay for ‘up to 20 gb’ when you can only download at 6 gb rate. Use a Free Download Checker on the Net to determine your speed.
TalkTalk install their own equipment in your exchange which at the start is no problem but when you want to leave TalkTalk your phone line has to be reconnected to the exchange that will cost you approx £100. If you go with them, be aware that their customer support is rather sad. If you ask a direct question, one that can only be answered with a Yes/No, they just work around it; must be part of their induction training. Another thing, whoever you go with, at the end of the contract that can be between 12 and 18 months, ask for a discount to stay with them.