[Private to Charlie/Justin]
What you mean by nobody and if there is reason she'd not want to be found by you. By saying a lot of us, I'm assuming you mean most of her friends are at least looking which means that she simply didn't just decide to up and take a vacation to be rid of you.
Let's see... She may be off the grid because there are Death Eaters running around unless they have managed to be captured, but since I haven't seen any snarky journal entries about how the Ministry is managing to actually do it's job, I doubt they have been.
As for why the Ministry would pick her up, there are too many reasons for that. She has a mouth on her and doesn't know when to shut up to authority, so she could have said something to piss them off and got picked up. There is also that brand she has on her arm which gives them the power to drag her in if she's perceived as part of any sort of suspicious activity or as having information to it. With her brand, her wand activity and her locations will be combed over and if any look suspicious, she'll be dragged in. Especially as they are all too eager for an excuse to take an ST's wand away.