I've recently decided to venture out of my comfort zone an see what was available on more 'manufacturer direct' mediums.
'Taobao' (taobao.com) is best viewed as a digital version of markets in China. Replica or fake clothing is readilly available, to a degree that is not comparable to typical 'western-accessible' sites. You can find Addidas Ultraboosts for as little as 100 yuan ($20) that use real boost material that the shoes are known for.
Taobao hasn't blown up internationally like other retailers because Taobao sellers dont typically ship internationally. To buy, you are essentially required to use a Taobao Agent (such as CSSBuy or SuperBuy), who act as a middleman between sellers and buyers to check the quality and sizing of items, send pictures to buyers and repackage to reduce space before shipping from their warehouses to the end user. Agents make the buying experience user friendly for the majority of international buyers.
If you are looking for unique clothing that doesnt make it to local sites, replica items or discounted alternative products, you might find it interesting buying from Taobao. If you want to know more specifics, I have found reddit communities such as /r/fashionreps and /r/sneakerreps are helpful resources that have an abundance of guides and reviews of items others had purchased.