[Perhaps the journal picks up the sound of Neville's arrival as he is unceremoniously deposited on the icy southern lake sometime in the dead of night. If not that, then it might catch the dull groaning as he slowly wakes and struggles to pull himself upright. If not that, then certainly the furious squeak from sneakers lacking traction on slippery ice would catch the journal's attention, as would the dull thudding as Neville collides with some child's forgotten snowman on the westernmost bank. A sharp intake of breath, then] No wand. Bastards. [In fact, even though Neville hasn't yet noticed the presence of the book at all, he seems perfectly aware that someone is listening, even if it isn't quite who he expects.]
It's still not enough! [The words, though a bit rasped and wheezing, are spoken with the stubbornness of one who rather expected this displacement.] You think you can just Portkey me someplace and be done with it? You won't get me -- not any of us -- to back down that easily. I know you're here -- show yourselves, you bloody cowards!
[The dead silence is less than encouraging. It means that if he wasn't being watched, then he'd been sent far enough that he wouldn't need supervision. Accio wand. [The incantation is intoned softly through clenched teeth. It doesn't escape him how ironic it was that in his desperation to recover his stolen wand he's resorted to a summoning spell that usually required the use of his wand in the first place. The spell fails spectacularly, leaving Neville to suppose his captors laughed, wherever they happen to be.
Still, the place he'd been sent certainly merits some investigation. If he'd been sent here via portkey, then some other innocuous-looking thing might well be the ticket home. It might appear off for a young, underdressed, blackeyed, fairly beaten and emaciated man to be picking up small stones with a thoughtful expression, but finding an alternate portkey is simply the most plausible way back to the more important matters he'd left at home.]