Well I've done this about four times now and I've never seen a tute on this so since I had to do this again today to eliminate the damn belt squeak I decided to take pics & make a tutorial.
DISCLAIMER: Some mechanical knowledge is required to do this. If you doubt your skills do not do this. I am not responsible for any damage to either you or your car.
This is for the I4
Step 1: Jack up the passenger side of you car & support it with jack stands. Make sure that you break the lugs before you jack it up. Don't remove them just break them so that you can remove them later.
http://i5.photobucket.com/albums/y19...ictures017.jpg
Step 2: After removing the wheel remove the belt guard that protects them. There are three bolts on the top of it & also three of those stupid plastic washer screws. Remove those also.
http://i5.photobucket.com/albums/y19...ictures018.jpg
Step 3:You 'll first want to remove the outer belt which are the power steering & A/C belt. You do this by loosning the tensioner that is between the above mentioned units by turning the bolt.
http://i5.photobucket.com/albums/y19...ictures021.jpg
Step 4: Now lets remove the inner belt (the smaller one). Get under the car & loosen the nut that holds the alternator. Its the only nut on it so you shouldn't have a problem locating it.
http://i5.photobucket.com/albums/y19...ictures020.jpg
Now go into the engine bay & loosen the bolt. Just keep wrenching at it until the threading on the other side is just about to go into the block looking piece. You want to also loosen the small bolt that is on the little block. This allows the alternator to slide up so that you can remove & install the belt easily. Remember do not remove the two blots completely from their respective places or you'll be there a while.
http://i5.photobucket.com/albums/y19...ictures022.jpg
The all you have to do is the opposite of this to install the belts. Just remember that the inner belt (ALT & W/P) must go on first, then your outer belt (A/C & P/S). Don't forget to get under the car after you tighten the alternator belt & torque the bolt under the alternator to spec.