1and1.com is good. They are different, but I’m pretty sure they are UK based. Good prices and huge.
Godaddy.com is also good. A little more expensive and better customer service. Not a fan of their ads…
I can highly recommend http://www.nethosted.co.uk/ – i’ve been using them for many years. They are a small, London based ISP. Their low-end plans are superb value for money and their support is second to none!
The only criticism I would have is that they tend to overcharge for domain names, so I use http://www.123-reg.co.uk/for that.
If I need a VPS I use http://www.linode.com/index.cfm – the raw power and pure flexibility are hard to beat. They are US based, but I find their Newark datacentre offers excellent bandwidth to the UK.