Whilst I'm pimping myself out, I am also working full time at Empora Ltd at the minute, as a Fashion Editor. It's the kind of website you don't realise you need, until you use it.
Self labelled "The Fashion Search Engine" it is home to over 2500 brands, ranging from McQueen to Topshop; you type in what you're after, and it shows you what's out there, whether it's on sale, possible similar items by different designers, then transfers you to the website to buy it. Geddit? So instead of trawling individual online stores, looking for the perfect pair of nude wedges - compare everything in one go, in one place.
Give it a whack why don't you?