http://zmodeler.nfscheats.com/
it has some alpha plugins quite interesting...is a pack...one of the pack does create a terrain from a heightfield bitmap (a greyscale image) .So it'd directly export as x file from there...
no animation.
it's in many languages,(download your preset) it seems :
Localization presets:
Russian preset by: Oleg M
Czech preset by: pedro)2(
Italian preset by: Daxter
Spanish preset by: PowerLeakage
German preset by: Besen
Nederlands preset by: Sander de Jong