Not only don't we know where the mind is; we don't know what, how many, why, how, or even whether it is. We get lots of handwaving, lots of assertion, little sense, and not even very sound grammar as a rule. 

At least we know what it would look like. It would look like abstract cause and effect. At one time I didn't have photographic evidence of this, but no problem now; I have none at present, being too absent minded.

 Some researchers and philosphers of mind seem to think it resides with the brain, as either an epiphenomenon (incidental side effect) or a purposeful product of the brain's activity; so that we could, at least in principle, have been brains in a vat.

 Others claim that it is a result of the interplay between an organism, having a large, appropriately organized brain, and its environment. Whence it cannot properly be said to be any well defined where.

 I think that when it comes to abstract terms like mind, the issue is not, and should not be, the existence (for what value of 'exist'?) of an equally abstract object; but the usefulness of the term, which naturally depends on the nature of the discourse. Many languages including my native Danish get by perfectly without any single word corresponding to the English 'mind'. So, to your question; where is it? My answer would be: in the English language...

 Nevertheless, that term does seem to have a reference, i.e. a usefulness in some discourses; where it is usually associated with a) understanding and knowledge, and b) intentional acts. Whence it could be said to be observable in such acts as exhibit some knowledge or understanding. And I'm sure that's all it'll ever look like.