Lensbase has launched a new "price matching" service in the UK. It aims to have the lowest prices in the UK market, and "will price match any product that is more competitively priced than ours!". They have a large stock backing them, which means same day shipment of most products.
Contact Lenses Price has price comparisons, but only for the U.S. market. Buyers in the UK should be aware that about 1 out of every 4 or 5 packages get "flagged" for import duty if you buy from the states, which will GREATLY increase your purchase price. Since LensBase is shipping from the EU, this is not a problem.
So far, I have not found something similar to Contact Lenses Price for the UK market - perhaps I should do that myself.