Tom, I purchased my deck, amplifier and speakers from Sonic Electronics; they have excellent prices. As Nick said, the front speakers are 6.5's, and the rears are 6X9's.
Here's the search results compatible with a 96' Protege.
For a very limited budget, here's my recommendations:
Fronts -
MTX Audio TN653 - $39. .... The lower model TN502's are
$30 at Crutchfield. Rears -
Rockford Fosgate Punch P1692 - $70 ....
$200 at Crutchfield. Amp to drive the rears -
Pyle PLA2378 - $65
Deck -
JVC KD-X50BT - $100 (Bluetooth and iPhone ready)
So that's $275 for a great budget friendly system. You could easily go without the amp for the rear speakers as the head unit will drive them, albeit not sufficiently (can't "push" them), which is why I suggested the amp. I was young once...
Peace
