Zara--my all time favorite store is Zara. their pieces range from high-fashion to casual chic to sexy conservative; there's really something for everyone. you can find something to wear for almost every occasion. plus, the prices are reasonable (very important when you're on a budget like me).
boutiques in my area: the boutiques in my area (The Dressing Room, Habit, Cheap n' Chic, Atik, Blush, Studio lx, etc...) all have great pieces that are priced pretty well. one thing i love about shopping at these boutiques is that they get new items in every week. most of them have a Facebook page where they post pictures of the new pieces. this way i know there will be things i like before i go to the store.
those are the stores i shop at most. i also love shopbop.com but can really only buy things when they're on sale (like the striped maxi dress i posted yesterday). i created an account on shopbop and favorite all the items i like. when they go on sale shopbop sends you an email. it's great! i love online shopping but usually end up returning the things i buy because they don't fit right, particularly bottoms.
speaking of online shopping, i ordered some things from Zara and they should come in today: