Congratulations on your promotion!!! I agree with the suggestions of Ann Taylor Loft and Ann Taylor---on sale!
Also, I have found GREAT bargains on some fabulous clothes from places like Ross and Marshalls. I am not sure if you have either or both of these stores in your area, but I have always had good luck. Keep in mind, patience is a virtue in these stores. More often than not, their racks are stuffed to capacity and you really have to look.
I just got some really nice dresses from my local Ross...regularly $80 each and I got them for $25 each. I am sucker for a bargain!!