People have already said it...
The sound insulation material inside your door panels is a lot of weight. That is your best bet for someone who thinks loosing a little pounds here and there makes a difference if you aren't tracking. Also speakers, headunits, cd changers, amps, and speaker wire are all excess if you want to start getting a bit more hardcore about it. Then look into removing the auxillary fan and case. Trunk lining and insulation, hood lining, and air conditioning.
Then if you start spending money look into a CF hood, CF trunk, CF panels (not your first LTW mods though), lighter cat back system exhaust, LTW flywheel, lighter battery (seriously), racing seats, and lighter rims.
If you are tracking try adn remove weight evenly betweent he front nad rear of the car. I know people who have removed 80 or so pounds from their cars but won't take out the spare and jack because it helps keep the balance of weight. Also if you live in a snow region keeping weight int he back will be to your advantage.