stall converter what??
 

can someone please just give me some info on stall converters?? my friend said that i should get one because i have an auto 97 gt...but wasn't really sure about them. What exactly do they do? Is it even worth buying one? Cost? where can i get one? is it just a bolt on or what?? do i need a whole other bunch of parts to put it on or is it a direct replacement?? just some info on it please...thanks