The owls in the universe of Harry Potter can track down anyone who is not disguised by any spell. But even on the official site, things aren't really explained. Would there be an explainable way that owls or any bird could (by explainable means) know a person's address and go there by command, without enhancing their intelligence, or making a new type of bird?
I don't believe its the owls that are doing the locating. Whether they are delivering a letter from home, a copy of the Daily Tattler, or an invitation to Hogwarts, the owls are carrying something.
I believe the objects are homing in on their intended recipient, and the owls are trained to follow a subtle pull or tug exerted by the object.
And, furthermore, this magic is never mentioned in HP World since it is as ubiquitous as turning on a water faucet is for us. It could be part of the sealing wax that seems to be used in every letter delivered in the movies. Or its in the quills, ink, or paper.
The owls seem to do it for knuts or out of love in the case of the family owl or personal familiars
Birds have been trained in the past to carry messages, the most famous example being pigeons. Birds would travel between their home and where they were fed, people on either end would attach messages to the legs of these homing pigeons.
However, as owls are birds of prey, i don’t think this would work as well. An owl might, rather than fly the long distance to get food, simply go out and hunt for it instead, causing the message to be lost. Further more, many owls have rather substantial talons and beaks capable of tearing flesh. Using pigeons is far safer and more convenient (as with owls you would need a thick leather glove or dedicated perch for them to land on in order to obtain the message, making things a little more cumbersome).
Also, consider this question about ravens. Whilst not quite the same as your question, it is very closely related. It is possible you could train owls to relay messages but they would be less effective than other birds.
Would there be an explainable way that owls or any bird could (by explainable means) know a person's address and go there by command?
The fowls, being magical, are able to read. Also, being specially related to Ravenclaw, they are more intelligent than the average Gryffindor (which is not very hard) or muggle. They know how to read a f... Magickin' phonebook.
(TBH Gryffindors are in average less intelligent than non magical birds as well, with only a handful famous exceptions).