i have a 1996 firebird on when i driving it the inside of the car smells of fuel not sure where to start to look of the probem ?

There are many explanations for smelling gas from your vehicle. 1) Gas leak (look for puddles underneath car when parked) 2) Leak in fuel injection line (you will smell gas during or immediately after driving your vehicle) 3) Leak in fuel-tank vent hose (this causes unburned gas to exit your fuel system as a vapor) 4) Bad fuel pressure regulator (can cause your vehicle to burn too rich or too thin a fuel mixture) *Other signs of a failing fuel pressure regulator include decreased power and lower than normal fuel efficiency of your vehicle* 5) Vehicles produced in the early 1980's or earlier will normally emit a slight gas odor after shut off. (This is due to fuel afterboil in the carburetor float bowl. Newer cars should not produce this smell after shut off as they are equipped with evaporative-emissions systems designed to prevent this.)

Iraebassett covered ost of the places to check but I know one more - the gas cap. These tend to fail sometimes and leak vapors that can make their way ito your car. A new one is only about $15 or try one from another similar vehicle and see if the smell goes away.