Hi Merlin,
Here's a couple for you, down in the dim dark recesses of Kent:
EM Models 
51 Camden Rd, Tunbridge Wells, TN1 2QE
Tel: 01892 536689 
Reasonable size shop, reasonable range of kits (Armour and Aircraft) and ephemera. Good range of tools, fillers etc, though limited to Humbrol and Tamiya paints. Not much in the way of after-market (PE, Decals etc) but very helpful and friendly staff will get most stuff to order in a few days.
Ballards
54, Grosvenor Rd, Tunbridge Wells, Kent TN1 2AS 
Tel: 01892 531803   
Small model shop with a mixed range, quite a few kits but very traditional - not much in the way of aftermarket stuff.
And not a model shop, but invaluable for Airplane-heads(like me!) is the Aviation Bookshop. Quite simply the biggest Aviation bookstore going, fantastic for research, and they have a glass case which they kindly let me put my models in (and sometimes even flog them!)
The Aviation Bookshop
33 Vale Rd
Tunbridge Wells
TN1 1BS
Telephone: 01892 539284
Website:  
www.aviation-bookshop.com