First i need to take the (front) door panels off... how do I do that?
Second What are the specs of stock speaker in the door (its an 99 alero).

This because i wanna put an amp the front speakers... or do you think buyin new ones is better?

thanx in advance

Marfless

Removing this is 3 steps:
a. First, look at the door. You'll see under the door-sill that there's a plastic piece with a small notch in it (right above the pocket on the door). Pry this off with a small object (probably your flat-head screwdriver). Remove the 2 phillips screws.
b. Pull the bottom part of the trim off (it has 2 clips on it; don't lose 'em).
c. Run the flat-head around the top piece of trim and it'll eventually pop off. The switches are a pain to get out (especially the driver's side window switch), but remove 'em and you'll have a much easier time.
Step 4 done!

far as specs on factory speaker, good question. you could push 50 watts to each fine but x-over so nothing under 120hz goes to them.

i push 300 rms to all of mine. been like that for a year or more.