I've lived in Paris for four months and a simple, but great thing to do is to buy a bottle of wine on just sit down at the Seine and relax. Another good place, though very touristic, is Montmartre and Sacre-Coeur, especially the steps in front of it. You can't watch a better sunset.
There is also a long "Canal", but i forgot the name. Same thing: get a bottle of wine and enjoy the "savoir-vivre".
I think the best place to shop, if you look for H+M, Zara and the rest, is Rue de Rivoli - in the centre, you can't miss it.
And remeber the sea is just one and half hours away (Trouville-Deauville - direct train) if you need a day to relax from all Parisian impressesions.
Looking forward to my year abroad - Paris is definitely my numer one at the moment!
Hopefully I could help you.
I loved Versailles. Utterly unnecessary and wonderfully gratuitous, but somehow it gave it an indulgent charm. Considering I've been there twice, I can remember very little I saw there. Typical places, plus some very nice random walks around the city, which is always the best way, IMHO.
I think the best attraction in Paris is the gay club, le Queen but don't be tempted by the Bains-Douche. When I went there it was absolutely ****. Apart from having photos to prove that J-Lo, the place has a nice decor and no atmosphere.
The airport at number 1
The Channel Tunnel at Number 2
My most favorite place in Paris is Quartier Latin. I have OD-ed on all the tourist attractions.
And during summer, Paris Plage, where I can play sports, meet French people and burn off the food.