Ok here are some basics to the kinda system you are looking for.
Head unit: you will most likely get a CD-player head unit, some things to look for are, "pre-outs" RMS wattage. Preouts are where the signal comes out for external amplifiers you might want to get later down the road for speakers, or subs. RMS wattage is the power the deck can put out consistently and not have any problems with indefinetly. Peak wattage isn't nearly as important as this. More power doesnt mean louder, its just cleaner music at the same volume. But most importantly, buy something you feel you can use, and meets all your criteria. Most pontiacs have the red dash lights, so matching red lights on a deck might be important to you. If you a volume **** or buttons is also a big thing, cause you'll use that the most. Which one is easiest for you to tink around with? If you have steering wheel controls in your car, and you might want to use them still, or maybe later on, there is an adapter for those to work with any deck that uses an infrared remote control. That is about $50.
Speakers: 2 way or 3 way or even 4 way isn't that important. That just means how many different speakers make up the whole speaker. 2 ways are just fine, and there is no problem with that, but make sure you are getting a quality speaker.
On most bonnevilles they have 6x9'* in the back, and a 5 1/4"component set of front speakers. This means the tweeter is seperate from the woofer, and these are generally higher quality speakers, and sound better then speakers with the tweeter on the woofer. If you want very high sound quality the the front speakers will make a HUGE difference in the sound. You want the front speakers to have a great over all sound, and the rears to fill in the back around you, and provide bass since they are bigger.
I would recommend spending this budget on your purchase
Head unit :$150-$175 Brands like Pioneer, Alpine, Rockford Fosgate, Sony, Kenwood, Clarion.
Front speakers (components) $150-$200 Brands Like JBL, Fosgate, Kicker, Boston Acoustics,
Rear speakers $75-$125 Any good pair at a good store will do the job.
'06 Vee Dub GTI 2 door Tornado Red
- 2.0 Turbocharged, Intercooled, Direct Injected, 6 Speed DSG, Underbody Aero, 17" Classix
- Moonroof, Bi-Xenon headlamps, Interlagos Plaid Sport Seats, 6 Disc In-dash, iPod integration, GTI Monster Mats (winter)
'93 Bonneville SE Purple Pearl H4U package - picked up June 23, 2003, Traded-in June 28, 2007...