Michelle Paver's 'Chronicles of Ancient Darkness' books are shaping up well - 'Wolf Brother', 'Spirit Walker' and 'Soul Eater'. They're set thousands of years ago.
Helena Pielichaty's 'Never Ever' is a modern girl hates boy story, but not sure whether you'd find it too much like the stuff you don't like. On the other hand, it's rather more than the chatty Georgia Nicholson/Princess Diaries type of thing. It tackles things like underage sex and drugs, but does it lightly. Pete Johnson also writes in a similar vein.
You might also like some of Kevin Brooks' work. It's more thriller than romance, and quite gritty. The boy/girl characters don't necessarily hate each other so much as just behave indifferently towards each other until one or the other characters realises the 'L' word has crept in. 'Lucas' and 'Candy' both have romantic elements, and I guarantee they will leave you in tears at the end, especially 'Lucas'.