Just got back from Paris last night! I loved it...it was SO gorgeous 
So, to shopping. Colette was way overrated, and I felt stupid for walking as far as I did to get there. I thought it was pretentious and trying WAY too hard to be cool.
What I loved was the Market at Place de Clichy (sic?) I bought some amazing trims for sewing.
Paris IMO is far more affordable than London, and everything is beautiful (seriously). I liked Hermes and the area around the Madeline Metro in General. I was dismayed by all the hyper commercial crap in the Champ Elyesses (Think the Disney store, McDonalds, blech). However, there is a very nice Tea salon called Laurdee there, with Napoleon III decor, which is very refreshing for a light meal. Also, for food, Fauchon by the Madeline Metro is *amazing*. Be careful though!
Back to clothes...The area around Pigalle is a bit grotty, but there are great fabrics and trims; it has a feel of the NYC garment district. I really enjoyed going to Gaultier on St. Honore.
Le Bon Marche was meh...like any other department store really. I tried to go to places I haven't been before, not that I could visit when I am in the UK or the US.
My favourite was BHV, probably because I am moving to a new flat, and they are having a decorating event. I bought a Louis XV door, and a counter top 
Across from the Opera house (Great performance by the way) M Opera is a shop called LA style. At first I was at the name, but went in in search of a cappuccino. I was pleasantly surprised; It was quite nice and stylish. And the girl on the ground floor made the best cappuccino I've ever had. Seriously.
I stayed in M Louise Michael and it is a very nice residential area with *very* nice boutiques.
I heard of a couple of retro shops and half price couture, but I ran out of time. I am going back probably in summer, so maybe then. Besides, there are several sample sales coming up in London, and my suitcase was screaming with pain as it was.
A word of warning...girls go around the tourist areas claiming to be war orphans from Bosnia. They are frauds, don't give them money. And I was picpocketed thrice. Including my mobile. I have a secret pocket, and I should of put everything in there. Alas.
I heard of Tati having an odd coolness, but I was disappointed (It is an uber cheap type of store, I can't compare it to anything in the UK really).
The best part was not the shopping though, it was the Opera! And all of the art...Versailles, and the love which had an amazing Ingress exhibit...he is a favourite.
Oh and one las thing...the Museum of costume had a great couture show on, including some of the original WWI "genie" dresses...amazing.
Can you tell I loved it? The architecture...swoon.
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i can't trust myself on trains and buses in my own city, never mind one i've only been to once. of course i read the thread, i just don't fancy going all over paris with an address book to hand looking for places i know i'll never find! 
