The rear springs are cake! Jack up both sides of the rear and put jackstands under the car. Remove the sway bar(2 bolts on each side). Place the jack under the end of the lower control arm where it attatches to the rearend, unbolt the control arm and lower the jack. Install the new spring and bolt the control arm back on. Repeat for the other side.
The front is a little tricky. You can do it several ways. First, you will need to remove the brake caliper and rotor. Edit: Forgot about the front sway bar, that needs unbolted too

. Then unbolt the strut from the spindle. If you are replacing the ball joints, use a ball joint separator(looks like a fork) to separate the spindle from the control arm.
Make sure you have a jack under the control arm before doing this, then lower the jack after the spindle is separated. Remove spring, change ball joints, reinstall.
If you don't want to replace your ball joints, you can remove the two bolts holding the contol arm to the k-member. That way is kind of a pain to get lined back up when reinstalling the springs, but it will save your ball joints.
Pick up a Haynes/Chiltons manual if you dont have one. I used that as a guide when changing my springs.