I have several tool shops listed on my favourites, sadly there does not seem to be one best one.
They all seem to specialise in selling some stuff cheaper than anybody else. Shopping around for known products is probably best.
I always check on fleabay as well, for power tools there are some great buys on 'reconditioned' tools.
I normally shop for tools online by putting the manufacturers part number in to Google Shopping. This is usually a good way of finding reasonable stores.
I like looking at the Hemingways and College Engineering kits but the people I always keep going back to are Arc Euro and Chronos. I've an axminster gift voucher waiting for me under the Christmas tree this year so will be perusing their catalogue again.
ANDY FROM WORKSHOPSHED, thanks for that list, it's got some really useful suppliers.
The engineers toolroom link is now top of my favorites list
However, I suspect it will not be a favorite of my wife, as I have found several rather large things in that site that I NEED! such as the rather nice milling machine and associated tooling The new bathroom plans might need to be scaled down a little as a result