Depends on the type of jack you have somewhat. When we lift my 68 coupe or fastback with the floor jack we lift the rear by placing the jack under the differential (with padding on the jack contact surface). Then we put one jackstand under the axle on each side, centered between the wheels and the differential. For the front, we usually put the jack under the center of the front frame rail. To avoid damage underneath, we usually have a small section of a 2x4 on the jack so we're not bending anything under there. Again, we place a jackstand on each front corner on the frame rails.
If you go to my website, there are some pictures of the fastback on jackstands. Both the undercarriage and exterior pages have photos of this.
right behind the front wheels and in front of the rear wheels on the rocker panels you will see an a couple areas an inch wide. That is where the jack from the trunk goes. The factory jack is a bit of a PITA so i use a scizzor jack under the axle or front A-Arm. If you don't own some form of floor jack there not a bad investment. You can get a hydrolic one on wheels from wallmart pretty cheap. I use a scizzor jack because there basically safe to work on the car while the car is on the jack and not need jack stands. A scizzer jack basically is a jack stand. I've never seen a hydrolic jack fail but it leaves you open to a major doofus by not tightening the release tight enough and have the jack leak down on you.
When i change the wheels with the facotry jack i don't use jack stands. I jack the car up and shove the wheel next to the jack so if the car gets pushed off the jack it will only fall to the wheel.