You need to find a 3 channel or 4 channel amplifier. (a 4 channel would be easier to find)
you do not need to run the full watt rating to any speaker, so I would recommend something along the lines of 100-200 x 4 for the amplifier. a 100 x 4 channel amplifier will provide 100 watts to each speaker, and 200 (or 400) watts to your woofer.
while hopefully not straining the electrical system of your car.
Without knowing the brand and model #'s of the woofer or speakers it is very difficult to recommend an amplifier that will work for you. Posting those up, and a $ budget will be very helpful.