Ok - since this post, and because I live in Wales' CAPITAL City but we HAVE NO LHBS IN THIS 'CITY'!!!! I've been to the Pontypridd shop, it is tiny and mostly devoted to organic & wholefoods. They have a sufficient selection of brewing essentials, such as yeast, campden tabbies, buckets, some Cellar 7 kits etc, and are absolutely LUVERRRLY people. I would certainly return if I am in the area, and the shop had absolutely gorgeous other items in addition to their brewing items....
I have also been to the brewing shop in Barry (
http://www.homebrewcentre.com/), which is the best LHBS I have visited so far - excellent range of equipment and essentials, are very kitted up for beers and ciders and have plenty of other brewing essentials such as eldeberries, sloes, and dried elderflowers, which I have been desperate to get hold of recently, and also the cheapest corks I have been able to find without shelling out £60, which I was bowled over with.
Extremely helpful and I will certainly return. This will be my LHBS from now on, despite 22 mile return journey lol. Check their website first for opening hours as they are not constantly open and in the event of change they have told me that they are very active in keeping everything very up to date for their customers on their website (unlike some other LHBS lol). Also give them a call to make sure they have what you want - they will get it in if they haven't got it. They only appeared to sell Beaverdale wine kits, which was the only potential criticism I had, but I have not asked them about this yet.
Otherwise I have also been to Wilkinsons Colchester Avenue (tiny range), and Tesco Culverhouse Cross (tiny range and scarily high prices lol)