How do I upgrade my sound system?

Well im sure that i can help you out considering i have the same exact car that you do but i have 2 12inch fusion powerplants in mine. If you only plan on running a single sub in the car you are better off getting a 12inch sub, take a look on ebay or craigslist, that would be your best bet for a cheap sub and amp, if you still want to keep your stock sub in the car along with something extra you should probably stick with a 10 inch sub. You can by a wiring kit at walmart for around $30. You will have to buy a roll of wiring though too, which you can get a 50 foot roll of 16 guage speaker wire at walmart for $19 because the wiring kit only comes with a ground wire, power wire, and a remote. The nice thing about Oldsmobile Aurora's is that the battery is under the back seat so you dont have to struggle to hide the wiring. The remote wire will have to be ran from the trunk to the door panel fuse box, which it will show you which fuse is for the radio, oh and you will have to buy a converter which i think is around $20 at walmart, it goes from speaker wire to rca's. You will have to run the 16-guage wire from your back speakers, the easiest way to get to them is by taking the panel off that has the carpeting on it, unless you want to do it the hard way and take the entire door panel off. Sorry to tell you but if you want a good quality sub and amp with all of the extra things that i have listed its gonna cost around $300 unless you can find someone where you live or over the internet that is selling for dirt cheap. if you have any more questions you can e-mail me at ryansleeter@yahoo.com