How to remove a car stereo which is secured in place?

I need to have a look at someones in-car stereo but need to know how to remove it as it is secured in place. What's the trick?How to remove a car stereo which is secured in place?
is it stock? or aftermarket. Typically there are special tools needed to remove radios, example- in my mazda 626 i had to buy a special tool that basically looked like a u shapped piece of metal, that would be inserted into the radio and it would pop right out, but like with my acura RSX the entire dash needed to come off. Check the vehicles specific guide, if your having a real hard time, its probably vehicle specific or you need that special toolHow to remove a car stereo which is secured in place?
every car is different but the cover around it should come off some how, once removed there should be 4 screws holding it in place. or a bracket on the back of the radio