It can be very hard to find a small fuel leak. Check around the car and see if you can pinpoint where it is coming from. Is the check engine light on? A fuel vapor leak from the EVAP system should turn the light on.
Check your fuel pressure regulator, pull the vacuum line off and smell for fuel when they fail you'll get gas fumes in the engine compartment. Here's a online guide to change the regulator http://bit.ly/6hCS5 and the parts run about $68 to $132 at the dealer or at autozone $55 http://www.autozone.com/N,14900165//shopping/partTypeResultSet.htm Hope this helps.
check the fuel tank area, The fuel pump is located in the fuel tank so there's a fuel pump seal that could be leaking and the lines coming from that area heading to the front of the vehicle also the filler neck could be leaking. better have a technician put your vehicle on a lift and locate the fuel leak.