Have you checked the inertia switch and see if it's being tripped somehow? Also, check to see if the wiring and the high-current fuse (located at the Power Distribution Center, underhood) is working correctly. Specifically, check to see if you have continuity (no continuity/voltage would indicate a bad ground). Lastly, check the vacuum line that runs from the vacuum tree (near the intake manifold) to the fuel pressure regulator.
As the fuel rail isn't getting pressure, but the pump is working, I'm thinking either you have a bad vacuum connection somewhere, that the fuel evaporative system or PCV system isn't working, or that the fuel pump/fuel pressure sending unit isn't working. Check all lines (flush them out if you have to, to make sure that they aren't cracked/leaking).
To make sure that you're getting fuel to the rail, simply turn the key to ON (but DO NOT START). Go to the Schraeder valve and push it down (use a rag to keep fuel from spraying everywhere). If you get gas at the valve, then the line has been properly pressurized. If the pump turns on, but you have no pressure, then something is keeping the pump from actually feeding fuel to the engine. As you've said that you've replaced the filter, I'm thinking that might not be it. However, make sure that it isn't installed backwards (yes, there is a proper way to install it--there should be the word "FLOW" with an arrow saying which way that the fuel flows. Install the filter with the arrow pointing towards the engine). If the filter is backwards, then the fuel pump will turn on, but no fuel will reach the fuel rail.
Lastly, check the charcoal canister vacuum connections are not cracked or leaking (this canister is located on the driver's side, underhood, near the radiator). For the PCV valve, this is located on the driver's side (intake side) of the engine; there should be an 'S'-curve hose leading to it. Pull it out and try to shake it. If it doesn't rattle, then it is clogged and needs to be replaced (less than $5 at most auto parts places).
