When you're not sure about where something is, you can say that it's "___ somewhere". For example:

It's over there somewhere.

I think she lives in the U.S. somewhere.

You can also say this in the order "somewhere ___":

It's somewhere over there.

But "___ somewhere" includes a small sense of not caring where the thing is. In other words, you're saying "It's near ___ but I don't really care exactly where it is." "Somewhere ___" doesn't have the same nuance.