Addition: While they mean the same when you are telling somebody - 'here is the thing you wanted, I am giving it to you/have just given it to you', they do not mean the same in other circumstances:
'Here you are' can also be used in the sense 'you always wanted to visit the King's court, and now here you are...' to refer to finally being in some place, be that a physical location, as in this example, or a place in life, eg: 'we always wanted to be court musicians, and now here we are'. 'Here you/we go cannot be used in these circumstances.
Similarly, 'Here we go'/'Here I go', a slightly different phrase to 'Here you go', can be used before embarking on something important, nerve-wracking, or incredible, eg. saying 'here we go' or 'here I go' before executing a difficult stunt on a skateboard. 'Here we are' or 'Here I am' could not be used in this way.
1Both are fine, with very little (if any) difference between them. – Andrew – 2016-11-19T17:55:46.203
Ngram says "here you are" is more common than "here you go" – Andrew – 2016-11-19T17:57:34.003
1
Possible duplicate of "There you go" or "There you are"
– FumbleFingers Reinstate Monica – 2016-11-19T18:15:09.740When used in contexts where the speaker is implicitly referencing the fact that the addressee now has whatever he needed, *go* is obviously more likely to carry a stronger implication of *Now you've got whatever you wanted, take it and go*, but that's not necessarily the case. For most contexts, here/there, are/go are really just stylistic preferences that all mean essentially the same thing. – FumbleFingers Reinstate Monica – 2016-11-19T18:21:16.007
@FumbleFingers where I live "here y'go" is pretty common, about as common as "here y'are". Both mean exactly the same thing, although as Colin Fine points out "here you go" could be considered a colloquialism of "here you are". – Andrew – 2016-11-19T21:53:20.950