You're right, she knows how to dress (or she has someone who knows how to dress her), but I can't help you with where she shops. What I can tell you is that she is going to have a show coming up called Kirstie Alley Big Life and they'll probably have some info in the credits.
First goal: under 180: 6/2/15
Second goal: 175 or below:
Third goal: 168 (no longer overweight):
Fourth goal: 161 (what I weighed before I fell off):
Fifth goal: below 160:
Final goal: 145-155: