When a commitment-phobic long-haul truckie falls for a city writer online, he must cross more than the Nullarbor to win her heart or lose her to a city slicker.

Having read the story, this is a great logline.

However, for non-Australians, the Nullarbor doesn't say much. Just say "the desert", or "1,675kms of desert"

I would also remove "online", as it sits awkward at ?the end of the sentence.

As it is a romance, or romantic comedy (can you do that?), I believe it would be stronger if you could give the writer a flaw. Even if she is really flawless!! :)