Wish you gave more info, like does this occur hot (after running) or cold (after parked awhile). I gather it cranks but won't fire. Hopefully the spark plugs and wires are up to date and not original. My answers are very general, and besides the parts you've already replaced I can only provide probable causes, which are:
the battery, loose or corroded battery cable, starter, starter relay, starter solenoid, coil wire, neutral safety switch, air charge sensor, fuel filter, fuel pressure regulator, fuel pump relay, throttle position sensor, coil, ignition switch, or ignition control module, in no particular order. If the key is chipped the reader in the steering column may be going out.
Intermittent troubles are the worst. Luckily, parts are inexpensive compared to most, but after having forked over for three parts, I'm sure your patience is thinning. Some of these parts can be removed and tested by an auto parts store, and others can be tested in place. It might be worth a $100+ to take it to a shop and have a diagnosis run if it can be done without a CEL, and also to have the fuel rail pressure tested.
Any check engine light? Can any more info be provided? Does the battery have good voltage? Is the fuel rail pressure good?