I use adjustable 3 ton jack stands (20 bucks at WalMart). Also NEVER jack your car up in gravel only stupid people like me try that. Luckily the jack fell over before I got under. And yes stuff behind the back wheels helps.
yeah, I am going to lift the car up this week, I have ramps but the car is too low for them, so I am going to use some wood to drive the car on first then the ramps. and next off I have no parking brake on the car, so bricks will have to do it for me.