@Deathstroke
Getting a major fucking headache out of all of this anyway -___- but since you're not doing it on purpose I'll answer this once.
Suna being target village is irrelevant, it'd be just the same if you went to kiri or konoha for example. People don't know or don't want to tell you? Nothing new about it, you would either have to just go search elsewhere, or then try picking people you suspect off one by one and trying to force it out of them, be it blackmail, torture, human path or whatever. Obviously trying to avoid being prosecuted a murdering criminal and taken down hard by authorities while you're at it of course. Survive and succeed, then you just have to find the target after.
There's literally nothing preventing this from working in my case in theory, its the exact same thing if you go after Gitsune or Eiko for example. Only difference is I've kept number of people who know I even exist to minimal numbers, because honestly that's how my character is, he doesn't give a flying fuck of being famous, doesn't trust people easily, and enjoys his peace. Difficult, but not impossible, and not to intentionally insult anyone but I don't consider myself particularly intelligent by any means, so if even I can figure shit like this out then its not impossible for others either.
As for sensing, exact methods vary depending on who you ask, but to give a general answer then yes, if you fill out two conditions its possible to sense a host.
1, you need a sufficiently advanced sensing technique such as mind's eye of the kagura, or wtf it was called, and you have to be actually proficient at the technique/sensing in general.
2, you have to know what you're actually looking for.
Neither of those however matters if the host in question is masking either the beasts chakra or their own chakra as a whole, be it through a kekkai, seal, jutsu or whatever else I can't think of on the fly.