Are you asking for suggestions where to shop? If so, Ann Taylor is good for sizes under 12. Loft has a few fairly conservative suit separates. New York and Co. skews young, but has some well designed and well priced tops. If your budget is higher, try the Nordstrom department called "Individualist". Macy's has a mid priced house line, too. If you enjoy the hunt for clothes, try TJ Maxx and Ross Dress for Less. In my area of the US, you can find twenty or so jackets on the rack, ten of which will be black, and one to three might fit you nicely.
If you are over 40, try Chico's or Coldwater Creek. Some of their things are more conservative in style than their ads show.