Ghoul touch states 'Fortitude negates' in the main stat-section. In the text nothing is said about that, except that targets that enter the area of the ghoul stench have a saving throw against the effects of the stench. Does that mean the main target is affected by the paralysis as long the touch attack hits, or does it have a saving throw in addition?
I read the rules as you need to hit with both a touch attack and the target must fail his saving throw for the spell to have an effect. The mother of all basic touch attack spells, the Cure/Inflict Wounds school of spells, requires a touch attack and a save. Ghoul Touch has two effects, the first of which being Paralysis. Paralysis is a very harsh effect, and since you can keep a touch spell "on hand" until you touch, the saving throw is the only chance a defending creature has to not get taken out of the fight.
Blindness-Deafness is an example of a spell that does not say in its description that there is a saving throw against the effects, because it says on the saving throw line that fortitude negates the effect. To say so again is not necessary. This is relevant to the Ghoul Touch spell because, like Blindness-Deafness, it says once that the spell effect is negated by a fortitude save, and only differs in that it has a secondary effect (the sickening effect). It is this second effect that is clarified by the spells description as also being negated by a saving throw.
A character who has been touched with the touch attack must make a save. If he fails, he is paralyzed for 1d6+2 rounds, and every living creature within 10' is repelled by the stench and must make another save.
Ghoul touch is worded kind of strangely, compared to other similar spells, one thing is clear: If a spell allows a save, then that spell describes exactly what that save means in it's description. The only mention of a fortitude save in the spell's description is in relation to the stench. Since the spell doesn't say that the target gets a save against the paralysis, they don't.
In response to Cthos's comment on the question: Chill touch has "Fortitude Partial" because the target takes one effect no matter what, and a secondary effect if they fail a save. Ghoul touch is "Fortitude Negates" because the main target takes the effect no matter what, but secondary targets get a save to negate. The difference is that any one target either takes the full effect targeting them, or takes nothing.