Clicking round a site for lighting and after exhaustive searching finding out that they don't sell what you are looking for is not the best policy. Below are a some of merchants who sell studio lighting. You will find studio lighting on all these sites and therefore will not waste time clicking through to lighting suppliers who only sell table lamps or garden lighting for instance. You could take the time to go through all the sites on this page as they all contain studio lighting.
Jessops
Buy studio lighting at Jessops. Studio flash, fabric backgrounds, studio brollies, studio reflectors, studio accessories, lamp/photoflood, studio diffusers, studio kits, paper backgrounds, studio softboxes.