It all depends on whether you have a BT line or not. If BT have to get involved, then you are looking at getting a BT line (I paid �125 for my installation, but I believe that you may be able to get it cheaper) and a BT contract.
After that, you will need to pay an activation fee (BT charge this to the ISP), I can't remember what it is (~�50) but you are on a monthly contract, which is why there isn't a free activation.
I trust you have a router that will work on a BT line.
After that, you are free to choose any of the EntaNet resellers (of which Vivaciti and UKFSN are but two). I use UKFSN (obviously) and I'm really happy with them. I get good speeds (slightly lower now after BT decided to disconnect me a few weeks ago) and my pings are excellent (sub25ms from Cheshire to the Gamesmajor servers).
You may also want to look at some of the other ISPs, IDNet, Sky, etc. It all depends on what you want from an ADSL connection. I find that UKFSN is good for me, but you may find that one of the others is good for you. The best advice we can give is to shop around till you find a good, reliable ISP that fits your budget and requirements.
Hope that helps.
Andy
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