May I recommend two sites to look for UK web streams?
www.radiofeeds.co.uk - includes listings for all licensed UK stations, but remember a lot of stations are UK only and you won't get them through this source.
www.vtuner.com - a listing of worldwide internet radio feeds including UK stations. I just purchased a Aluratek wifi alarm clock radio which uses their listings to keep its radio up to date. The radio only supports windows media and streaming mp3, so BBC domestic stations which stream internationally using Real technology. For that I could get a Grace wifi radio. But the vtuner.com site lists the streams as being geographically restricted or not so you can know whether to bother firing them up if they're listed UK only or US only or otherwise.
Capital Gold is just known as Gold now and poses itself more as a national station on DAB with local opt outs on MW - even in London. Still not a bad station and quite a good example of how an oldies station should sound in today's market. Radio's being rationalized big time in the UK: lots of local names are disappearing and being replaced with the Heart or Magic or Gold branding. Stations are only obliged to provide 4 hours a weekday of live/local programming in peak time so stations often have PM drive local and the rest is networked. If anything, it's the BBC who is getting more local: Southern Counties Radio is being split soon into BBC Radio Surrey and BBC Radio Sussex (ironically Southern Counties Radio was formed from a merger of BBC Radio Surrey & Radio Sussex).