boohoo.com - great deals on apparel. They usually have a coupon code on the site that you can apply at checkout, so you'll get a discount each time you shop.
GoJane has a great selection of shoes, which is what I first started shopping there for. Then I took me a while to realize they also had clothes I loved. GoJane's campaigns keep up with the latest trends and you can shop by each specific trend, or by look. They have a pretty awesome blog, as well that features giveaways and more. Also, check out their Facebook where they give out a pair of shoes every week.
H&M just recently launched their e-commerce site. I was pretty excited because I wanted this option forever, since we don't have one here in New Orleans. We'll be getting one soon, though. :)
Tobi has 30% new arrivals daily, and 50% off your order for new members. You get another 50% off for inviting 5 friends. Sign up now via my link.
Forever21 for a while, but they made a huge comeback for me. They've got great street style looks, which are some of my favorite.
Last but certainly not least, eBay is one of my absolute favorite places to shop for things like accessories. I usually buy purses, jewelry and shoes from this site. I think I'll do an eBay post later on.