Its really nice to get great service from people and here are some people that I would recommend you try
Minimi Models - Lewis Davis in Worcestershire is always willing to chat about existing an upcoming releases.
Shrewsbury Model Centre - helpful bunch of boys
Hannants - good online shop, quick service
eBay - love it or loathe it - I love it. There are some great traders - look for very high feedback scored and descriptions of stuff that sounds like the person knows what they are talking about
Bankside Systems - these guys have turned my laymans drivel into a working on-line shop to support this website (that they set up as well). That in itself is worth a mention, a medal and a long lie down!!
Two Fat Lardies - a recent discovery and a very good find!! Check them out (site details in the LINX section)
JadlamModelRacing - I have used these guys for slot cars and wargame bits. Always great service. 2nd hand stuff always well priced and is good working order where motors etc are concerned.
Hattons - They advertise themselves as the largest model shop in the UK but I went there recently and its just a warehouse!! That aside, they have a massive stock list and great website. ALL my railway stuff comes from them as they are always on the top line when it comes to price and delivery. Highly recommended
Grubby Tanks - sent an email regarding their AFVs recently and got a very cordial reply prompting an order. I cannot say anything higher than that!!
Britannia Miniatures - part of grubby. Good range of models and a very user-friendly website. Ideal for technodinosaurs like me!