I spent a week in Paris in 2000....it was the most magnificent thing I've every done....like you, it was an all girl trip....the highlights for me were:
Mussee d'Orsay (Orsay Museum)....amazing modern art. I liked it better than the Louvre....even though the Louvre is a "must do" as well....can't go to Paris without seeing Mona Lisa or Michealangelo's David...
http://www.sacre-coeur-montmartre.com/us/index.html
The whole Montmarte area is amazing.....that's an area with a lot of local artists. There is a restaurant there called Mere Catherine in the Montmarte area that is just amazing. They have local talent sing there every night.....bottles of wine on every table... very, very good food! The profiteroles that I had for dessert (I had no idea what they were at the time) are a chocolate fantasy I love to revisit....The time we spent at Montmarte was probably my favorite part of the trip.....
We went to Ash Wednesday services at Notre d*m while we were there....it was a very moving, spiritual experience. Notre Dom is a must see.....
Walking down Champs d'elyse is amazing.....all the high end designer shops.....it's definitely where all of the pretty people are....I felt like a toad, but still loved every minute of seeing it!
You must go to the top of the Eiffel Tower during the day AND at night....seeing the lights of the city from the top of the tower is beyond amazing!! Everything was still lit up from the Millenium celebration when we were there, but I'll bet it's incredible no matter when you go.
Hit the small patisseries for breakfast......the pastries are to die for and you can eat for a little bit of nothing.
The only thing we did that I was disappointed in was a visit to the palace at Versaille.....I don't know what I expected, but it just didn't hit me. You're moved through it like cattle and it just didn't impress me..
http://www.pere-lachaise.com/perelachaise.php?lang=en
Pere Lachaise cemetary is a great trip, too......if you like that sort of thing....and of course, visit Jim Morrison's grave.
We were very, very fortunate as we had a guide that was an American who had lived in Paris for fifteen years....she spoke fluent French and English.....
If I think of more, I'll add it, but honestly....it was a trip I still love to revisit looking at pictures whenever I can.....no matter what, every time I get together with this group of friends....we always end up talking about Paris. I do so hope to share it with my daughter someday!