The main sales start on Black Friday, the day after Thanksgiving, but I don't think they drag on for weeks as they do here.
We prefer the Premium Outlets North and always seem to come back from there laden with stuff. You can check which stores they have on their website
http://www.premiumoutlets.com/outlets/outlet.asp?id=58 and I see that they are open on New Year's Day. You can get there on the SDX bus from Paris or a taxi would be about $15-20 each way.
I see on their site that they have "After Holiday Sales" from 26 Dec till 1 Jan.
There are other outlets to the south as well as Town Square, the Miracle Mile and the Forum Shoppes.
luci